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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 field_to_long(value):
 """ Converts given value to long if possible, otherwise None is returned. :param value: :return: """

        if isinstance(value, (int, long)):
            return long(value)
        elif isinstance(value, basestring):
            return bytes_to_long(from_hex(value))
        else:
            return None