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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 hexadecimal(token):
 """ Convert a strip of hexadecimal numbers into binary data. @type token: str @param token: String to parse. @rtype: str @return: Parsed string value. """

        token = ''.join([ c for c in token if c.isalnum() ])
        if len(token) % 2 != 0:
            raise ValueError("Missing characters in hex data")
        data = ''
        for i in compat.xrange(0, len(token), 2):
            x = token[i:i+2]
            d = int(x, 16)
            s = struct.pack('<B', d)
            data += s
        return data