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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 create_subnet(self, subnet, prefix, **kwargs):
 """Create a subnet. :param subnet: Name of subnet to be created. :type subnet: str :param prefix: Routing prefix of subnet to be created. :type prefix: str :param \*\*kwargs: See the REST API Guide on your array for the documentation on the request: **POST subnet/:subnet** :type \*\*kwargs: optional :returns: A dictionary describing the created subnet. :rtype: ResponseDict .. note:: prefix should be specified as an IPv4 CIDR address. ("xxx.xxx.xxx.xxx/nn", representing prefix and prefix length) .. note:: Requires use of REST API 1.5 or later. """

        data = {"prefix": prefix}
        data.update(kwargs)
        return self._request("POST", "subnet/{0}".format(subnet), data)