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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 remove_armor(armored_data):
 """Decode armored data into its binary form."""

    stream = io.BytesIO(armored_data)
    lines = stream.readlines()[3:-1]
    data = base64.b64decode(b''.join(lines))
    payload, checksum = data[:-3], data[-3:]
    assert util.crc24(payload) == checksum
    return payload