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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(addr):
 """Decode a segwit address."""

    hrpgot, data = bech32_decode(addr)
    # if hrpgot != hrp:
    if hrpgot not in BECH32_VERSION_SET:
        return (None, None)
    decoded = convertbits(data[1:], 5, 8, False)
    if decoded is None or len(decoded) < 2 or len(decoded) > 40:
        return (None, None)
    if data[0] > 16:
        return (None, None)
    if data[0] == 0 and len(decoded) != 20 and len(decoded) != 32:
        return (None, None)
    return (data[0], decoded)