class_docstr: Class that creates a callable object to retrieve events in a
  blocking way.
docstr: For baseclass, do nothing but collect events
docstr_tok: ["For","baseclass",",","do","nothing","but","collect","events"]
code: def post_event(self):
      """For baseclass, do nothing but collect events"""
      pass
  
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import six
  import matplotlib.lines
  import logging
label_desc: Use image node_id 3 for calling the BlockingInput obj's underlying member method code with example usage: obj.post_event() without return types