I'm using PLY. Here is one of my states from parser.out:

state 3

    (5) course_data -> course .
    (6) course_data -> course . course_list_tail
    (3) or_phrase -> course . OR_CONJ COURSE_NUMBER
    (7) course_list_tail -> . , COURSE_NUMBER
    (8) course_list_tail -> . , COURSE_NUMBER course_list_tail

  ! shift/reduce conflict for OR_CONJ resolved as shift
    $end            reduce using rule 5 (course_data -> course .)
    OR_CONJ         shift and go to state 7
    ,               shift and go to state 8

  ! OR_CONJ         [ reduce using rule 5 (course_data -> course .) ]

    course_list_tail               shift and go to state 9

I want to resolve this as:

if OR_CONJ is followed by COURSE_NUMBER:
    shift and go to state 7
else:
    reduce using rule 5 (course_data -> course .)

How can I fix my parser file to reflect this? Do I need to handle a syntax error by backtracking and trying a different rule?