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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 get(self, sg_id):
 """Fetches the security group. :returns: SecurityGroup object corresponding to sg_id """

        secgroup = self.client.show_security_group(sg_id).get('security_group')
        sg_dict = self._sg_name_dict(sg_id, secgroup['security_group_rules'])
        return SecurityGroup(secgroup, sg_dict)