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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 set_composite_filter(filter_proto, op, *filters):
 """Set composite filter contraint in the given datastore.Filter proto message. Args: filter_proto: datastore.Filter proto message op: datastore.CompositeFilter.Operation filters: vararg list of datastore.Filter Returns: the same datastore.Filter. Usage: """

  filter_proto.Clear()
  cf = filter_proto.composite_filter
  cf.op = op
  for f in filters:
    cf.filters.add().CopyFrom(f)
  return filter_proto