':type policy_arn: string
:param policy_arn: The ARN of the policy to detach
:type group_name: string
:param group_name: Group to detach the policy from'

def detach_group_policy(self, policy_arn, group_name):

    params = {'PolicyArn': policy_arn, 'GroupName': group_name}
    return self.get_response('DetachGroupPolicy', params)
