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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 add_properties(entity_proto, property_dict, exclude_from_indexes=None):
 """Add values to the given datastore.Entity proto message. Args: entity_proto: datastore.Entity proto message. property_dict: a dictionary from property name to either a python object or datastore.Value. exclude_from_indexes: if the value should be exclude from indexes. None leaves indexing as is (defaults to False if value is not a Value message). Usage: Raises: TypeError: if a given property value type is not supported. """

  for name, value in property_dict.iteritems():
    set_property(entity_proto.properties, name, value, exclude_from_indexes)