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  • Eclipse+PyDev+GAE memcache error

    - by bocco
    I've started using Eclipe+PyDev as an environment for developing my first app for Google App Engine. Eclipse is configured according to this tutorial. Everything was working until I start to use memcache. PyDev reports the errors and I don't know how to fix it: Error: Undefined variable from import: get How to fix this? Sure, it is only PyDev checker problem. Code is correct and run on GAE. UPDATE: I'm using PyDev 1.5.0 but experienced the same with 1.4.8. My PYTHONPATH includes (set in Project Properties/PyDev - PYTHONPATH): C:\Program Files\Google\google_appengine C:\Program Files\Google\google_appengine\lib\django C:\Program Files\Google\google_appengine\lib\webob C:\Program Files\Google\google_appengine\lib\yaml\lib UPDATE 2: I took a look at C:\Program Files\Google\google_appengine\google\appengine\api\memcache\__init__.py and found get() is not declared as memcache module function. They use the following trick to do that (I didn't hear about such possibility): _CLIENT = None def setup_client(client_obj): """Sets the Client object instance to use for all module-level methods. Use this method if you want to have customer persistent_id() or persistent_load() functions associated with your client. Args: client_obj: Instance of the memcache.Client object. """ global _CLIENT var_dict = globals() _CLIENT = client_obj var_dict['set_servers'] = _CLIENT.set_servers var_dict['disconnect_all'] = _CLIENT.disconnect_all var_dict['forget_dead_hosts'] = _CLIENT.forget_dead_hosts var_dict['debuglog'] = _CLIENT.debuglog var_dict['get'] = _CLIENT.get var_dict['get_multi'] = _CLIENT.get_multi var_dict['set'] = _CLIENT.set var_dict['set_multi'] = _CLIENT.set_multi var_dict['add'] = _CLIENT.add var_dict['add_multi'] = _CLIENT.add_multi var_dict['replace'] = _CLIENT.replace var_dict['replace_multi'] = _CLIENT.replace_multi var_dict['delete'] = _CLIENT.delete var_dict['delete_multi'] = _CLIENT.delete_multi var_dict['incr'] = _CLIENT.incr var_dict['decr'] = _CLIENT.decr var_dict['flush_all'] = _CLIENT.flush_all var_dict['get_stats'] = _CLIENT.get_stats setup_client(Client()) Hmm... Any idea how to force PyDev to recognize that?

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  • PyML 0.7.2 - How to prevent accuracy from dropping after stroing/loading a classifier?

    - by Michael Aaron Safyan
    This is a followup from "Save PyML.classifiers.multi.OneAgainstRest(SVM()) object?". The solution to that question was close, but not quite right, (the SparseDataSet is broken, so attempting to save/load with that dataset container type will fail, no matter what. Also, PyML is inconsistent in terms of whether labels should be numbers or strings... it turns out that the oneAgainstRest function is actually not good enough, because the labels need to be strings and simultaneously convertible to floats, because there are places where it is assumed to be a string and elsewhere converted to float) and so after a great deal of hacking and such I was finally able to figure out a way to save and load my multi-class classifier without it blowing up with an error.... however, although it is no longer giving me an error message, it is still not quite right as the accuracy of the classifier drops significantly when it is saved and then reloaded (so I'm still missing a piece of the puzzle). I am currently using the following custom mutli-class classifier for training, saving, and loading: class SVM(object): def __init__(self,features_or_filename,labels=None,kernel=None): if isinstance(features_or_filename,str): filename=features_or_filename; if labels!=None: raise ValueError,"Labels must be None if loading from a file."; with open(os.path.join(filename,"uniquelabels.list"),"rb") as uniquelabelsfile: self.uniquelabels=sorted(list(set(pickle.load(uniquelabelsfile)))); self.labeltoindex={}; for idx,label in enumerate(self.uniquelabels): self.labeltoindex[label]=idx; self.classifiers=[]; for classidx, classname in enumerate(self.uniquelabels): self.classifiers.append(PyML.classifiers.svm.loadSVM(os.path.join(filename,str(classname)+".pyml.svm"),datasetClass = PyML.VectorDataSet)); else: features=features_or_filename; if labels==None: raise ValueError,"Labels must not be None when training."; self.uniquelabels=sorted(list(set(labels))); self.labeltoindex={}; for idx,label in enumerate(self.uniquelabels): self.labeltoindex[label]=idx; points = [[float(xij) for xij in xi] for xi in features]; self.classifiers=[PyML.SVM(kernel) for label in self.uniquelabels]; for i in xrange(len(self.uniquelabels)): currentlabel=self.uniquelabels[i]; currentlabels=['+1' if k==currentlabel else '-1' for k in labels]; currentdataset=PyML.VectorDataSet(points,L=currentlabels,positiveClass='+1'); self.classifiers[i].train(currentdataset,saveSpace=False); def accuracy(self,pts,labels): logger=logging.getLogger("ml"); correct=0; total=0; classindexes=[self.labeltoindex[label] for label in labels]; h=self.hypotheses(pts); for idx in xrange(len(pts)): if h[idx]==classindexes[idx]: logger.info("RIGHT: Actual \"%s\" == Predicted \"%s\"" %(self.uniquelabels[ classindexes[idx] ], self.uniquelabels[ h[idx] ])); correct+=1; else: logger.info("WRONG: Actual \"%s\" != Predicted \"%s\"" %(self.uniquelabels[ classindexes[idx] ], self.uniquelabels[ h[idx] ])) total+=1; return float(correct)/float(total); def prediction(self,pt): h=self.hypothesis(pt); if h!=None: return self.uniquelabels[h]; return h; def predictions(self,pts): h=self.hypotheses(self,pts); return [self.uniquelabels[x] if x!=None else None for x in h]; def hypothesis(self,pt): bestvalue=None; bestclass=None; dataset=PyML.VectorDataSet([pt]); for classidx, classifier in enumerate(self.classifiers): val=classifier.decisionFunc(dataset,0); if (bestvalue==None) or (val>bestvalue): bestvalue=val; bestclass=classidx; return bestclass; def hypotheses(self,pts): bestvalues=[None for pt in pts]; bestclasses=[None for pt in pts]; dataset=PyML.VectorDataSet(pts); for classidx, classifier in enumerate(self.classifiers): for ptidx in xrange(len(pts)): val=classifier.decisionFunc(dataset,ptidx); if (bestvalues[ptidx]==None) or (val>bestvalues[ptidx]): bestvalues[ptidx]=val; bestclasses[ptidx]=classidx; return bestclasses; def save(self,filename): if not os.path.exists(filename): os.makedirs(filename); with open(os.path.join(filename,"uniquelabels.list"),"wb") as uniquelabelsfile: pickle.dump(self.uniquelabels,uniquelabelsfile,pickle.HIGHEST_PROTOCOL); for classidx, classname in enumerate(self.uniquelabels): self.classifiers[classidx].save(os.path.join(filename,str(classname)+".pyml.svm")); I am using the latest version of PyML (0.7.2, although PyML.__version__ is 0.7.0). When I construct the classifier with a training dataset, the reported accuracy is ~0.87. When I then save it and reload it, the accuracy is less than 0.001. So, there is something here that I am clearly not persisting correctly, although what that may be is completely non-obvious to me. Would you happen to know what that is?

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  • Can a CLSID be different for the same program installed on two different machines?

    - by uberjumper
    I am using comtypes to generate wrappers for a certain com library. I am having certain issues with a few things, that are not being generated properly. I can get around this by doing the missing work, manually. However can i depend on the fact that CLSID's will not change? Lets say: I install a program with the com library Foo 1.0, now i install the exact same version of that program on another PC, will the CLSID's of the interfaces change? This might be a terribly dumb question.

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  • TypeError: unbound method make_request() must be called with XX instance, but how?

    - by Dave
    Running the code below I get E TypeError: unbound method make_request() must be called with A instance as first argument (got str instance instead) I dont want to set make_request method as static, I want to call it from an instance of an object. The example http://pytest.org/latest/fixture.html#fixture-function # content of ./test_smtpsimple.py import pytest @pytest.fixture def smtp(): import smtplib return smtplib.SMTP("merlinux.eu") def test_ehlo(smtp): response, msg = smtp.ehlo() assert response == 250 assert "merlinux" in msg assert 0 # for demo purposes My code """ """ import pytest class A(object): """ """ def __init__(self, name ): """ """ self._prop1 = [name] @property def prop1(self): return self._prop1 @prop1.setter def prop1(self, arguments): self._prop1 = arguments def make_request(self, sex): return 'result' def __call__(self): return self @pytest.fixture() def myfixture(): """ """ A('BigDave') return A def test_validateA(myfixture): result = myfixture.make_request('male') assert result =='result'

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  • pyparsing ambiguity

    - by Claudiu
    I'm trying to parse some text using PyParser. The problem is that I have names that can contain white spaces. So my input might look like this: Joe Bob Jimmy Foo Joe decides to eat. Bob decides to not eat. Jimmy Foo decides to eat. How can I create a parser for the decides to eat line? If I create my name parser naively, meaning with alphabetic characters plus space characters, then it will match the entire line.

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  • Why do socket.makefile objects fail after the first read for UDP sockets?

    - by Eli Courtwright
    I'm using the socket.makefile method to create a file-like object on a UDP socket for the purposes of reading. When I receive a UDP packet, I can read the entire contents of the packet all at once by using the read method, but if I try to split it up into multiple reads, my program hangs. Here's a program which demonstrates this problem: import socket from sys import argv SERVER_ADDR = ("localhost", 12345) sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) sock.bind(SERVER_ADDR) f = sock.makefile("rb") sock.sendto("HelloWorld", SERVER_ADDR) if "--all" in argv: print f.read(10) else: print f.read(5) print f.read(5) If I run the above program with the --all option, then it works perfectly and prints HelloWorld. If I run it without that option, it prints Hello and then hangs on the second read. I do not have this problem with socket.makefile objects when using TCP sockets. Why is this happening and what can I do to stop it?

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  • Requires a valid Date or x-amz-date header?

    - by Jordan Messina
    I'm getting the following error when attempting to upload a file to S3: S3StorageError: <?xml version="1.0" encoding="UTF-8"?> <Error><Code>AccessDenied</Code><Message>AWS authentication requires a valid Date or x-amz-date header</Message><RequestId>7910FF83F3FE17E2</RequestId><HostId>EjycXTgSwUkx19YNkpAoY2UDDur/0d5SMvGJUicpN6qCZFa2OuqcpibIR3NJ2WKB</HostId></Error> I'm using Django with Django-Storages and Imagekit My S3 settings in my settings.py looks as follows: locale.setlocale(locale.LC_TIME, 'en_US') DEFAULT_FILE_STORAGE = 'backends.s3.S3Storage' AWS_ACCESS_KEY_ID = '************************' AWS_SECRET_ACCESS_KEY = '*****************************' AWS_STORAGE_BUCKET_NAME = 'static.blabla.com' AWS_HEADERS = { 'x-amz-date': datetime.datetime.utcnow().strftime('%a, %d %b %Y %H:%M:%S GMT'), 'Expires': 'Thu, 15 Apr 2200 20:00:00 GMT', } from S3 import CallingFormat AWS_CALLING_FORMAT = CallingFormat.SUBDOMAIN Thanks for any help you can give!

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  • How do I create self-relationships in polymorphic inheritance in Elixir and Pylons?

    - by Turukawa
    I am new to programming and am following the example in the Pylons documentation on creating a Wiki. The database I want to link to the wiki was created with Elixir so I rewrote the Wiki database schema and have continued from there. In the wiki there is a requirement for a Navigation table which is inherited by Pages and Sections. A section can have many pages, while a page can only have one section. In addition, each sibling node can be chain-referenced to each other. So: Nav has "section" (OneToMany) and "before" (OneToOne - to reference preceeding node) Page has "section" (ManyToOne - many pages in one section) and inherits "before" Section inherits all from Nav The code I've written looks like this: class Nav(Entity): using_options(inheritance='multi') name = Field(Unicode(30), default=u'Untitled Node') path = Field(Unicode(255), default=u'') section = OneToMany('Page', inverse='section') after = OneToOne('Nav', inverse='before') before = OneToMany('Nav', inverse='after') class Page(Nav): using_options(inheritance='multi') content = Field(UnicodeText, nullable=False) posted = Field(DateTime, default=now()) title = Field(Unicode(255), default=u'Untitled Page') heading = Field(Unicode(255)) tags = ManyToMany('Tag') comments = OneToMany('Comment') section = ManyToOne('Nav', inverse='section') class Section(Nav): using_options(inheritance='multi') Errors received on this: sqlalchemy.exc.OperationalError: (OperationalError) table nav has no column named aftr_id u'INSERT INTO nav (name, path, aftr_id, row_type) VALUES (?, ?, ?, ?)' I've also tried: before = ManyToMany('Nav', inverse='before') on Nav in the hopes this might break the problem, but also not. The original SQLAlchemy code from the tutorial for these declarations is as follows: nav_table = schema.Table('nav', meta.metadata, schema.Column('id', types.Integer(), schema.Sequence('nav_id_seq', optional=True), primary_key=True), schema.Column('name', types.Unicode(255), default=u'Untitled Node'), schema.Column('path', types.Unicode(255), default=u''), schema.Column('section', types.Integer(), schema.ForeignKey('nav.id')), schema.Column('before', types.Integer(), default=None), schema.Column('type', types.String(30), nullable=False) ) page_table = schema.Table('page', meta.metadata, schema.Column('id', types.Integer, schema.ForeignKey('nav.id'), primary_key=True), schema.Column('content', types.Text(), nullable=False), schema.Column('posted', types.DateTime(), default=now), schema.Column('title', types.Unicode(255), default=u'Untitled Page'), schema.Column('heading', types.Unicode(255)), ) section_table = sa.Table('section', meta.metadata, schema.Column('id', types.Integer, schema.ForeignKey('nav.id'), primary_key=True), ) orm.mapper(Nav, nav_table, polymorphic_on=nav_table.c.type, polymorphic_identity='nav') orm.mapper(Section, section_table, inherits=Nav, polymorphic_identity='section') orm.mapper(Page, page_table, inherits=Nav, polymorphic_identity='page', properties={ 'comments':orm.relation(Comment, backref='page', cascade='all'), 'tags':orm.relation(Tag, secondary=pagetag_table) }) Any help is much appreciated.

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  • Start PyGTK cellrenderer edit from code

    - by mkotechno
    I have a treeview with an editable CellRendererText: self.renderer = gtk.CellRendererText() self.renderer.set_property('editable', True) But now I need to launch the edition from code instead from user, this is to focus the user attention in the fact he just created a new row and needs to be named. I tried this but does not work: self.renderer.start_editing( gtk.gdk.Event(gtk.gdk.NOTHING), self.treeview, str(index), gtk.gdk.Rectangle(), gtk.gdk.Rectangle(), 0) Neither does not throw errors, but the documentation about for what is each argument is not clear, in fact I really don't know if start_editing method is for this. All suggestions are welcome, thanks.

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  • Django stupid mark_safe?

    - by Mark
    I wrote this little function for writing out HTML tags: def html_tag(tag, content=None, close=True, attrs={}): lst = ['<',tag] for key, val in attrs.iteritems(): lst.append(' %s="%s"' % (key, escape_html(val))) if close: if content is None: lst.append(' />') else: lst.extend(['>', content, '</', tag, '>']) else: lst.append('>') return mark_safe(''.join(lst)) Which worked great, but then I read this article on efficient string concatenation (I know it doesn't really matter for this, but I wanted consistency) and decided to update my script: def html_tag(tag, body=None, close=True, attrs={}): s = StringIO() s.write('<%s'%tag) for key, val in attrs.iteritems(): s.write(' %s="%s"' % (key, escape_html(val))) if close: if body is None: s.write(' />') else: s.write('>%s</%s>' % (body, tag)) else: s.write('>') return mark_safe(s.getvalue()) But now my HTML get escaped when I try to render it from my template. Everything else is exactly the same. It works properly if I replace the last line with return mark_safe(unicode(s.getvalue())). I checked the return type of s.getvalue(). It should be a str, just like the first function, so why is this failing?? Also fails with SafeString(s.getvalue()) but succeeds with SafeUnicode(s.getvalue()). I'd also like to point out that I used return mark_safe(s.getvalue()) in a different function with no odd behavior.

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  • Proper way to set object instance variables

    - by ensnare
    I'm writing a class to insert users into a database, and before I get too far in, I just want to make sure that my OO approach is clean: class User(object): def setName(self,name): #Do sanity checks on name self._name = name def setPassword(self,password): #Check password length > 6 characters #Encrypt to md5 self._password = password def commit(self): #Commit to database >>u = User() >>u.setName('Jason Martinez') >>u.setPassword('linebreak') >>u.commit() Is this the right approach? Should I declare class variables up top? Should I use a _ in front of all the class variables to make them private? Thanks for helping out.

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  • Allow run-time configuration of web service url using ATL soap and sproxy-generated proxy class

    - by Odrade
    I have a Visual C++ application that communicates with an ASP.NET web service via ATL Soap. The client application uses an sproxy-generated proxy class for the communication. Looking at the generated proxy class, I noticed that the url for the web service is hard-coded in numerous places. It would be preferable for the url to be configurable at run-time (e.g. stored in a config file). Could anyone recommend a method for doing this? It doesn't look like the class generated by sproxy is amenable to hand-editing.

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  • Regex: Matching a space-joined list of words, excluding last whitespace

    - by Jesper
    How would I match a space separated list of words followed by whitespace and some optional numbers? I have this: >>> import re >>> m = re.match('(?P<words>(\w+\s+)+)(?P<num>\d+)?\r\n', 'Foo Bar 12345\r\n') >>> m.groupdict() {'num': '12345', 'words': 'Foo Bar '} I'd like the words group to not include the last whitespace(s) but I can't figure this one out. I could do a .strip() on the result but that's not as much fun :) Some strings to test and wanted result: 'Foo & Bar 555\r\n' => {'num': '555', 'words': 'Foo & Bar'} 'Hello World\r\n' => {'num': None, 'words': 'Hello World'} 'Spam 99\r\n' => {'num': 99, 'words': 'Spam'} 'Number 1 666\r\n' => {'num': 666, 'words': 'Number 1'}

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  • Infrastructure for a "news-feed"

    - by ensnare
    I'd like to offer a news-feed like feature for users of our website. When the user logs in, he is shown a list of the latest updates across various areas of the site. I'm afraid that this is going to be difficult to scale. What are some networking / database topologies that can support a scalable infrastructure without having lots of copies of the same data? (I'd like to make it so if a piece of data is updated, each user's feed is also updated live). Thanks for the assistance and advice.

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  • I need to know what link is clicked, how do i get these variables with cherrypy?

    - by user291071
    Lets say I display 3 links, I want to accomplish 2 things, know which link is clicked, and record this choice in a list/pickle or txt file but also capture this variable in cherrypy so I can perform another action. How do I do this? Its been suggested that I use a query string which makes sense but I can't get the querystring variable to cherrypy to use for further actions. So would anyone have a simple code of cherrypy with lets say 2 pages and have one page display 2 links with a querystring in each and the second page able to get that value?

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  • Pythonic / itertools way to go through a dict?

    - by dmd
    def reportCSV(t): ret = '' for ev in t: for p in t[ev]: for w in t[ev][p]: ret += ','.join((ev, p, w, t[ev][p][w])) + '\n' return ret What is a more pythonic way to do this, e.g. using itertools or the like? In this case I'm just writing it out to a CSV file. t is a dict t[ev] is a dict t[ev][p] is a dict t[ev][p][w] is a float I'm not sure how I'd use itertools.product in this case.

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  • Fixing color in scatter plots in matplotlib

    - by ajhall
    Hi guys, I'm going to have to come back and add some examples if you need them, which you might. But, here's the skinny- I'm plotting scatter plots of lab data for my research. I need to be able to visually compare the scatter plots from one plot to the next, so I want to fix the color range on the scatter plots and add in a colorbar to each plot (which will be the same in each figure). Essentially, I'm fixing all aspects of the axes and colorspace etc. so that the plots are directly comparable by eye. For the life of me, I can't seem to get my scatter() command to properly set the color limits in the colorspace (default)... i.e., I figure out my total data's min and total data's max, then apply them to vmin, vmax, for the subset of data, and the color still does not come out properly in both plots. This must come up here and there, I can't be the only one that wants to compare various subsets of data amongst plots... so, how do you fix the colors so that each data keeps it's color between plots and doesn't get remapped to a different color due to the change in max/min of the subset -v- the whole set? I greatly appreciate all your thoughts!!! A mountain-dew and fiery-hot cheetos to all! -Allen

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  • getting keyboard events with pyqt

    - by Moayyad Yaghi
    hello i converted recently from wxpython to pyqt and im still facing alot of problems since im still noob in pyqt so is it possible to detected if user pressed (CTRL+key ) in pyqt ? and how ? i've been trying to find an answer for this for 3 days . if you know website or a good place to learn pyqt, it will be highly appreciated thanx in advance

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  • Django: Serving Media Behind Custom URL

    - by TheLizardKing
    So I of course know that serving static files through Django will send you straight to hell but I am confused on how to use a custom url to mask the true location of the file using Django. http://stackoverflow.com/questions/2681338/django-serving-a-download-in-a-generic-view but the answer I accepted seems to be the "wrong" way of doing things. urls.py: url(r'^song/(?P<song_id>\d+)/download/$', song_download, name='song_download'), views.py: def song_download(request, song_id): song = Song.objects.get(id=song_id) fsock = open(os.path.join(song.path, song.filename)) response = HttpResponse(fsock, mimetype='audio/mpeg') response['Content-Disposition'] = "attachment; filename=%s - %s.mp3" % (song.artist, song.title) return response This solution works perfectly but not perfectly enough it turns out. How can I avoid having a direct link to the mp3 while still serving through nginx/apache? EDIT 1 - ADDITIONAL INFO Currently I can get my files by using an address such as: http://www.example.com/music/song/1692/download/ But the above mentioned method is the devil's work. How can I accomplished what I get above while still making nginx/apache serve the media? Is this something that should be done at the webserver level? Some crazy mod_rewrite? http://static.example.com/music/Aphex%20Twin%20-%20Richard%20D.%20James%20(V0)/10%20Logon-Rock%20Witch.mp3

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  • Loading Files in AppEngine

    - by Chris M
    I've got a tiny bit of code to display a file in app.yaml - url: /(.*\.(gif|png|jpg)) static_files: static/\1 upload: static/(.*\.(gif|png|jpg)) in main.py ... class ShowImage(webapp.RequestHandler): def get(self): rootpath = os.path.dirname(__file__) file = rootpath + "/static/tracker.gif"; fh=open(file, 'r') self.response.out.write(fh.read()) fh.close ... I can see the files gone up by going to my *.appspot.com/tracker.gif (as per the app.yaml) But using *.appspot.com/showimage returns Traceback (most recent call last): File "/base/python_lib/versions/1/google/appengine/ext/webapp/__init__.py", line 510, in __call__ handler.get(*groups) File "/base/data/home/apps/APPNAME/2.341131266814384624/main.py", line 170, in get fh=open(file, 'r') IOError: [Errno 2] No such file or directory: '/base/data/home/apps/APPNAME/2.341131266814384624/static/tracker.gif'

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  • Map only certain parts of the class to a database using SQLAlchemy?

    - by Az
    When mapping an object using SQLAlchemy, is there a way to only map certain elements of a class to a database, or does it have to be a 1:1 mapping? Example: class User(object): def __init__(self, name, username, password, year_of_birth): self.name = name self.username = username self.password = password self.year_of_birth = year_of_birth Say, for whatever reason, I only wish to map the name, username and password to the database and leave out the year_of_birth. Is that possible and will this create problems? Edit - 25/03/2010 Additionally, say I want to map username and year_of_birth to a separate database. Will this database and the one above still be connected (via username)?

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  • How to "signal" interested child processes (without signals)?

    - by Teddy
    I'm trying to find a good and simple method to signal child processes (created through SocketServer with ForkingMixIn) from the parent process. While Unix signals could be used, I want to avoid them since only children who are interested should receive the signal, and it would be overkill and complicated to require some kind of registration mechanism to identify to the parent process who is interested. (Please don't suggest threads, as this particular program won't work with threads, and thus has to use forks.)

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  • SQLAlchemy custom query column

    - by thrillerator
    I have a declarative table defined like this: class Transaction(Base): __tablename__ = "transactions" id = Column(Integer, primary_key=True) account_id = Column(Integer) transfer_account_id = Column(Integer) amount = Column(Numeric(12, 2)) ... The query should be: SELECT id, (CASE WHEN transfer_account_id=1 THEN -amount ELSE amount) AS amount FROM transactions WHERE account_id = 1 OR transfer_account_id = 1 My code is: query = Transaction.query.filter_by(account_id=1, transfer_account_id=1) query = query.add_column(func.case(...).label("amount") But it doesn't replace the amount column. Been trying to do this with for hours and I don't want to use raw SQL.

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