python - How do you check if an object is an instance of 'file'? -

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it used in python (2.6) 1 ask:

isinstance(f, file)

but in python 3.0 file removed.

what proper method checking see if variable file now? what'snew docs don't mention this...

def read_a_file(f)     try:         contents = f.read()     except attributeerror:         # f not file

substitute whatever methods plan use read. optimal if expect passed file object more 98% of time. if expect passed non file object more 2% of time, correct thing is:

def read_a_file(f):     if hasattr(f, 'read'):         contents = f.read()     else:         # f not file

this if did have access file class test against. (and fwiw, have file on 2.6) note code works in 3.x well.


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