readlines problems - Newbie

[John Purser]

Hello,

I've got a little function:
def FindLine(Record):
     im1_Dif.seek(0)
     im1_Dif.readlines(Record - 1)
     test = im1_Dif.readline()
     print test

When I call it I wind up with the same record in "test" whether I pass it 1
or 10.  The readlines line reads a huge chunk of text with no regard for
lines at all.  I have no idea what is causing this.  Where can I find the
documentation on the file methods?  I can't find them in the documentation.
Can anyone tell me what's going on here?

John Purser