docs: def ng_call_ctrl_function(self, element, func, params='', return_out=False):
          """
          :Description: Will execute controller function with provided parameters.
          :Warning: This will only work for angular.js 1.x.
          :Warning: Requires angular debugging to be enabled.
          :param element: Element for browser instance to target.
          :param func: Function to execute from angular element controller.
          :type func: string
          :param params: String (naked) args, or list of parameters to pass to target function.
          :type params: string, tuple, list
          :param return_out: Return output of function call otherwise None
          :type return_out: bool
          """
          if isinstance(params, string_types):
              param_str = params
          elif isinstance(params, (tuple, list)):
              param_str = self.__serialize_params(params)
          else:
              raise ValueError('Invalid type specified for function parameters')
          exec_str = 'angular.element(arguments[0]).controller().%s(%s);' % (func, param_str)
          if return_out:
              return self.__type2python(
                  self.browser.execute_script('return {}'.format(exec_str), element))
          else:
              self.browser.execute_script(exec_str, element)