title: how do i define python's list with dict in grpc's protobuf?
body: <p>in .proto:</p>
  
  <pre><code>message HelloReplyList { repeated string message = 1; }
  </code></pre>
  
  <p>the following code works fine</p>
  
  <pre><code>def SayHelloList(self, request, context):
      l = ['a', 'b', 'c']
      return helloworld_pb2.HelloReplyList(message=l)
  </code></pre>
  
  <p>the following code works error:
  TypeError: {'a': '1'} has type dict, but expected one of: bytes, unicode</p>
  
  <pre><code>def SayHelloList(self, request, context):
      d = [{'a': '1'}, {'b': '2'}]
      return helloworld_pb2.HelloReplyList(message=d)
  </code></pre>
  
  <p>if i want to use <code>[{'a':'1'},{'b':'2'}]</code>. how do i define in <code>.proto</code>?</p>