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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 ListGrrBinaries(context=None):
 """Lists all registered Grr binaries."""


  items = context.SendIteratorRequest("ListGrrBinaries", None)
  return utils.MapItemsIterator(
      lambda data: GrrBinary(data=data, context=context), items)