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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 reverse_hash(hash, hex_format=True):
 """ hash is in hex or binary format """

    if not hex_format:
        hash = hexlify(hash)
    return "".join(reversed([hash[i:i+2] for i in range(0, len(hash), 2)]))