[BEAM-9812] Fixing bug causing pipelines requiring temp tables to not…

… work

sdks/python/apache_beam/io/gcp/bigquery_tools.py

@@ -175,14 +175,18 @@ def parse_table_reference(table, dataset=None, project=None):
  Returns:
  A TableReference object from the bigquery API. The object has the following
  attributes: projectId, datasetId, and tableId.
+ If the input is a TableReference object, a new object will be returned.
 
  Raises:
  ValueError: if the table reference as a string does not match the expected
  format.
  """
 
  if isinstance(table, bigquery.TableReference):
- return table
+ return bigquery.TableReference(
+ projectId=table.projectId,
+ datasetId=table.datasetId,
+ tableId=table.tableId)
  elif callable(table):
  return table
  elif isinstance(table, value_provider.ValueProvider):