text: # Copyright 2021 Google LLC
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #      http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  """Interface for an PwRPC (Pigweed RPC) echo capability."""
  import abc
  from gazoo_device.capabilities.interfaces import capability_base
  
  
  class PwRPCEchoBase(capability_base.CapabilityBase):
    """Pigweed RPC echo capability."""
  
    @abc.abstractmethod
    def echo(self, msg: str) -> str:
      """Sends a message to the echo endpoint and returns the response back."""
  