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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def fn_check_full(fn):
 """Check for file existence Avoids race condition, but slower than os.path.exists. Parameters fn : str Input filename string. Returns ------- status True if file exists, False otherwise. """

    status = True 
    if not os.path.isfile(fn): 
        status = False
    else:
        try: 
            open(fn) 
        except IOError:
            status = False
    return status