api: Implement GET /messages/<message_id>/history.

zulip/zulip/__init__.py

@@ -748,6 +748,16 @@ class Client(object):
             method='DELETE'
         )
 
+    def get_message_history(self, message_id):
+        # type: (int) -> Dict[str, Any]
+        '''
+            See examples/message-history for example usage.
+        '''
+        return self.call_endpoint(
+            url='messages/{}/history'.format(message_id),
+            method='GET'
+        )
+
     def get_events(self, **request):
         # type: (**Any) -> Dict[str, Any]
         '''

zulip/zulip/examples/message-history

@@ -0,0 +1,19 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+import argparse
+
+import zulip
+
+usage = """message-history <message_id> [options]
+
+Example: message-history 42
+"""
+
+parser = zulip.add_default_arguments(argparse.ArgumentParser(usage=usage))
+parser.add_argument('message_id', type=int)
+options = parser.parse_args()
+
+client = zulip.init_from_options(options)
+
+print(client.get_message_history(options.message_id))