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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_property_filter(filter_proto, name, op, value):
 """Set property filter contraint in the given datastore.Filter proto message. Args: filter_proto: datastore.Filter proto message name: property name op: datastore.PropertyFilter.Operation value: property value Returns: the same datastore.Filter. Usage: """

  filter_proto.Clear()
  pf = filter_proto.property_filter
  pf.property.name = name
  pf.op = op
  set_value(pf.value, value)
  return filter_proto