parameters: (self, functions)
docstring: Constructor.
  
      Args:
        functions: A `Functions` object.
docstring_summary: Constructor.
docstring_tokens: Constructor .
function: def __init__(self, functions):
      """Constructor.
  
      Args:
        functions: A `Functions` object.
      """
      self._functions = functions
      # Maps tuples in the form (file_path, called_function_name, line_number)
      # to `Location` protos.
      self._location_key_to_location = {}
function_tokens: def __init__ ( self , functions ) : self . _functions = functions # Maps tuples in the form (file_path, called_function_name, line_number) # to `Location` protos. self . _location_key_to_location = { }