class_docstr: Class that creates a callable object to retrieve mouse clicks in a
  blocking way.
  
  This class will also retrieve keyboard clicks and treat them like
  appropriate mouse clicks (delete and backspace are like mouse button 3,
  enter is like mouse button 2 and all others are like mouse button 1).
docstr: Will be called for any event involving button 3.
  Button 3 removes the last click.
docstr_tok: ["Will","be","called","for","any","event","involving","button","3",".","Button","3","removes","the","last","click","."]
code: def mouse_event_pop(self, event):
      """
      Will be called for any event involving button 3.
      Button 3 removes the last click.
      """
      # Remove this last event
      BlockingInput.pop(self, -1)
  
      # Now remove any existing clicks if possible
      if len(self.events) > 0:
          self.pop(event, -1)
  
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import six
  import matplotlib.lines
  import logging
label_desc: Use image node_id 7 for calling the BlockingMouseInput obj's underlying member method code with example usage: obj.mouse_event_pop(event) without return types