remove mutable defualt

Author: sharinetmc

parsons/google/google_bigquery.py

@@ -456,7 +456,19 @@ def copy_from_gcs(
                 Other arguments to pass to the underlying load_table_from_uri
                 call on the BigQuery client.
         """
-        self._validate_copy_inputs(if_exists=if_exists, data_type=data_type)
+        self._validate_copy_inputs(
+            if_exists=if_exists,
+            data_type=data_type,
+            accepted_data_types=[
+                "csv",
+                "json",
+                "parquet",
+                "datastore_backup",
+                "newline_delimited_json",
+                "avro",
+                "orc",
+            ],
+        )
 
         job_config = self._process_job_config(
             job_config=job_config,
@@ -1565,25 +1577,13 @@ def _fetch_query_results(self, cursor) -> Table:
         ptable = petl.frompickle(temp_filename)
         return Table(ptable)
 
-    def _validate_copy_inputs(
-        self,
-        if_exists: str,
-        data_type: str,
-        accepted_data_types: list[str] = [
-            "csv",
-            "json",
-            "parquet",
-            "datastore_backup",
-            "newline_delimited_json",
-            "avro",
-            "orc",
-        ],
-    ):
+    def _validate_copy_inputs(self, if_exists: str, data_type: str, accepted_data_types: list[str]):
         if if_exists not in ["fail", "truncate", "append", "drop"]:
             raise ValueError(
                 f"Unexpected value for if_exists: {if_exists}, must be one of "
                 '"append", "drop", "truncate", or "fail"'
             )
+
         if data_type not in accepted_data_types:
             raise ValueError(f"Only supports {accepted_data_types} files [data_type = {data_type}]")