code: def assert_complete(self):
      pass
  
imports: from sympy.core.singleton import S
  from sympy.core.symbol import Symbol
  from sympy.core.sympify import sympify
  from sympy.core.numbers import Integer
label_desc: Use image node_id 17 for calling the PlotInterval obj's underlying member method code with example usage: obj.assert_complete() without return types