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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 is_base64(string):
 """Determines whether or not a string is likely to be base64 encoded binary nonsense"""

    return (not re.match('^[0-9]+$', string)) and \
        (len(string) % 4 == 0) and \
        re.match('^[A-Za-z0-9+/]+[=]{0,2}$', string)