code: def ping(proxy=None, hostport=None):
      
      schema = {
          'type': 'object',
          'properties': {
              'status': {
                  'type': 'string'
              },
          },
          'required': [
              'status'
          ]
      }
  
      assert proxy or hostport, 'Need either proxy handle or hostport string'
      if proxy is None:
          proxy = connect_hostport(hostport)
  
      resp = {}
  
      try:
          resp = proxy.ping()
          resp = json_validate( schema, resp )
          if json_is_error(resp):
              return resp
  
          assert resp['status'] == 'alive'
  
      except ValidationError as e:
          if BLOCKSTACK_DEBUG:
              log.exception(e)
  
          resp = {'error': 'Server response did not match expected schema.  You are likely communicating with an out-of-date Blockstack node.', 'http_status': 502}
          return resp
  
      except socket.timeout:
          log.error("Connection timed out")
          resp = {'error': 'Connection to remote host timed out.', 'http_status': 503}
          return resp
  
      except socket.error as se:
          log.error("Connection error {}".format(se.errno))
          resp = {'error': 'Connection to remote host failed.', 'http_status': 502}
          return resp
  
      except Exception as ee:
          if BLOCKSTACK_DEBUG:
              log.exception(ee)
  
          log.error("Caught exception while connecting to Blockstack node: {}".format(ee))
          resp = {'error': 'Failed to contact Blockstack node.  Try again with `--debug`.', 'http_status': 500}
          return resp
  
      return resp
docs: rpc_ping
      Returns {'alive': True} on succcess
      Returns {'error': ...} on error