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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 _RemoveAllFlagAppearances(self, name):
 """Removes flag with name for all appearances. A flag can be registered with its long name and an optional short name. This method removes both of them. This is different than __delattr__. Args: name: Either flag's long name or short name. Raises: UnrecognizedFlagError: When flag name is not found. """

    flag_dict = self.FlagDict()
    if name not in flag_dict:
      raise exceptions.UnrecognizedFlagError(name)
    flag = flag_dict[name]
    names_to_remove = {name}
    names_to_remove.add(flag.name)
    if flag.short_name:
      names_to_remove.add(flag.short_name)
    for n in names_to_remove:
      self.__delattr__(n)