parameters: (self, a=None, b=None)
docstring: dummy method - to be overwritten by child class
docstring_summary: dummy method - to be overwritten by child class
docstring_tokens: dummy method - to be overwritten by child class
function: def tracer(self, a=None, b=None):
          """dummy method - to be overwritten by child class"""
function_tokens: def tracer ( self , a = None , b = None ) :