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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def assert_no_leftovers(self):
 """Generate an error if there are leftover members."""

    leftovers = []
    for name in self._members.keys():
      if name in self._members and name not in self._documented:
        leftovers.append(name)
    if leftovers:
      raise RuntimeError("%s: undocumented members: %s" %
                         (self._title, ", ".join(leftovers)))