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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 add_lambda_integration(self, path, method, integration_uri, method_auth_config=None, api_auth_config=None, condition=None):
 """ Adds aws_proxy APIGW integration to the given path+method. :param string path: Path name :param string method: HTTP Method :param string integration_uri: URI for the integration. """


        method = self._normalize_method_name(method)
        if self.has_integration(path, method):
            raise ValueError("Lambda integration already exists on Path={}, Method={}".format(path, method))

        self.add_path(path, method)

        # Wrap the integration_uri in a Condition if one exists on that function
        # This is necessary so CFN doesn't try to resolve the integration reference.
        if condition:
            integration_uri = make_conditional(condition, integration_uri)

        path_dict = self.get_path(path)
        path_dict[method][self._X_APIGW_INTEGRATION] = {
                'type': 'aws_proxy',
                'httpMethod': 'POST',
                'uri': integration_uri
        }

        method_auth_config = method_auth_config or {}
        api_auth_config = api_auth_config or {}
        if method_auth_config.get('Authorizer') == 'AWS_IAM' \
           or api_auth_config.get('DefaultAuthorizer') == 'AWS_IAM' and not method_auth_config:
            self.paths[path][method][self._X_APIGW_INTEGRATION]['credentials'] = self._generate_integration_credentials(
                method_invoke_role=method_auth_config.get('InvokeRole'),
                api_invoke_role=api_auth_config.get('InvokeRole')
            )

        # If 'responses' key is *not* present, add it with an empty dict as value
        path_dict[method].setdefault('responses', {})

        # If a condition is present, wrap all method contents up into the condition
        if condition:
            path_dict[method] = make_conditional(condition, path_dict[method])