Drop f-strings for compatibility

Author: vinceatbluelabs

pybigquery/sqlalchemy_bigquery.py

@@ -364,7 +364,7 @@ def _split_table_name(full_table_name):
         elif len(table_name_split) == 3:
             project, dataset, table_name = table_name_split
         else:
-            raise ValueError(f"Did not understand table_name: {full_table_name}")
+            raise ValueError("Did not understand table_name: {}".format(full_table_name))
 
         return (project, dataset, table_name)
 
@@ -386,14 +386,13 @@ def _table_reference(self, provided_schema_name, provided_table_name,
                 project_id_from_schema = provided_schema_name_split[0]
                 dataset_id_from_schema = provided_schema_name_split[1]
             else:
-                raise ValueError(f"Did not understand schema: {provided_schema_name}")
-            # TODO: Get a test for an else statement here
+                raise ValueError("Did not understand schema: {}".format(provided_schema_name))
         if (dataset_id_from_schema and dataset_id_from_table and
            dataset_id_from_schema != dataset_id_from_table):
-            raise ValueError(f"dataset_id specified in schema and table_name disagree: got {dataset_id_from_schema} in schema, and {dataset_id_from_table} in table_name")
+            raise ValueError("dataset_id specified in schema and table_name disagree: got {} in schema, and {} in table_name".format(dataset_id_from_schema, dataset_id_from_table))
         if (project_id_from_schema and project_id_from_table and
            project_id_from_schema != project_id_from_table):
-            raise ValueError(f"project_id specified in schema and table_name disagree: got {project_id_from_schema} in schema, and {project_id_from_table} in table_name")
+            raise ValueError("project_id specified in schema and table_name disagree: got {} in schema, and {} in table_name".format(project_id_from_schema, project_id_from_table))
         project_id = project_id_from_schema or project_id_from_table or client_project
         dataset_id = dataset_id_from_schema or dataset_id_from_table or self.dataset_id