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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 size_of_type(abi_type):
 """ Returns size in bits of abi_type """

    if 'string' in abi_type:
        return None
    if 'byte' in abi_type:
        return None
    if '[' in abi_type:
        return None
    if abi_type == 'bool':
        return 8
    if abi_type == 'address':
        return 160
    return int(re.sub(r"\D", "", abi_type))