"bagpipe-looking-glass bgp" results in "error code 500"

[Thomas Morin]

With current master code, but probably some earlier versions as well, we have this:

# bagpipe-looking-glass bgp
Error code 500: A server error occurred. Please contact the administrator.

In bagpipe-bgp logs, we have the following error:

Traceback (most recent call last):
  File "/usr/lib64/python2.7/wsgiref/handlers.py", line 85, in run
    self.result = application(self.environ, self.start_response)
  File "/usr/lib/python2.7/site-packages/pecan/middleware/recursive.py", line 56, in __call__
    return self.application(environ, start_response)
  File "/usr/lib/python2.7/site-packages/pecan/core.py", line 840, in __call__
    return super(Pecan, self).__call__(environ, start_response)
  File "/usr/lib/python2.7/site-packages/pecan/core.py", line 683, in __call__
    self.invoke_controller(controller, args, kwargs, state)
  File "/usr/lib/python2.7/site-packages/pecan/core.py", line 604, in invoke_controller
    result = self.render(template, result)
  File "/usr/lib/python2.7/site-packages/pecan/core.py", line 425, in render
    return renderer.render(template, namespace)
  File "/usr/lib/python2.7/site-packages/pecan/templating.py", line 23, in render
    return encode(namespace)
  File "/usr/lib/python2.7/site-packages/pecan/jsonify.py", line 133, in encode
    return _instance.encode(obj)
  File "/usr/lib64/python2.7/json/encoder.py", line 207, in encode
    chunks = self.iterencode(o, _one_shot=True)
  File "/usr/lib64/python2.7/json/encoder.py", line 270, in iterencode
    return _iterencode(o, 0)
  File "/usr/lib/python2.7/site-packages/pecan/jsonify.py", line 127, in default
    return jsonify(obj)
  File "/usr/lib/python2.7/site-packages/singledispatch.py", line 210, in wrapper
    return dispatch(args[0].__class__)(*args, **kw)
  File "/usr/lib/python2.7/site-packages/pecan/jsonify.py", line 122, in jsonify
    return _default.default(obj)
  File "/usr/lib/python2.7/site-packages/pecan/jsonify.py", line 108, in default
    return JSONEncoder.default(self, obj)
  File "/usr/lib64/python2.7/json/encoder.py", line 184, in default
    raise TypeError(repr(o) + " is not JSON serializable")
TypeError: <bound method Manager.get_lg_route_counts of Manager> is not JSON serializable
127.0.0.1 - - [10/Oct/2019 13:01:48] "GET /looking-glass/bgp HTTP/1.1" 500 59