I'm confused by how the length of a string is calculated when expandtabs is used. I thought expandtabs replaces tabs with the appropriate number of spaces (with the default number of spaces per tab being 8). However, when I ran the commands using strings of varying lengths and varying numbers of tabs, the length calculation was different than I thought it would be (i.e., each tab didn't always result in the string length being increased by 8 for each instance of "/t"). Below is a detailed script output with comments explaining what I thought should be the result of the command executed above. Would someone please explain the how the length is calculated when expand tabs is used? IDLE 2.6.5 >>> s = '\t' >>> print len(s) 1 >>> #the length of the string without expandtabs was one (1 tab counted as a single space), as expected. >>> print len(s.expandtabs()) 8 >>> #the length of the string with expandtabs was eight (1 tab counted as eight spaces). >>> s = '\t\t' >>> print len(s) 2 >>> #the length of the string without expandtabs was 2 (2 tabs, each counted as a single space). >>> print len(s.expandtabs()) 16 >>> #the length of the string with expandtabs was 16 (2 tabs counted as 8 spaces each). >>> s = 'abc\tabc' >>> print len(s) 7 >>> #the length of the string without expandtabs was seven (6 characters and 1 tab counted as a single space). >>> print len(s.expandtabs()) 11 >>> #the length of the string with expandtabs was NOT 14 (6 characters and one 8 space tabs). >>> s = 'abc\tabc\tabc' >>> print len(s) 11 >>> #the length of the string without expandtabs was 11 (9 characters and 2 tabs counted as a single space). >>> print len(s.expandtabs()) 19 >>> #the length of the string with expandtabs was NOT 25 (9 characters and two 8 space tabs). >>>