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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 decode_int(v):
 """decodes and integer from serialization"""

    if len(v) > 0 and (v[0] == b'\x00' or v[0] == 0):
        raise Exception("No leading zero bytes allowed for integers")
    return big_endian_to_int(v)