docs: def load(target, source_module=None):
      """Get the actual implementation of the target."""
      module, klass, function = _get_module(target)
      if not module and source_module:
          module = source_module
      if not module:
          raise MissingModule(
              "No module name supplied or source_module provided.")
      actual_module = sys.modules[module]
      if not klass:
          return getattr(actual_module, function)
  
      class_object = getattr(actual_module, klass)
      if function:
          return getattr(class_object, function)
      return class_object