create a new sanitized tuple because tuple is immutable

packages/db/elastic_migrations/migrate_from_elastic.py

@@ -231,18 +231,14 @@ async def insert_recommendations(db_conn, recommendations, original_ids):
 
 
 async def insert_into_postgres(insert_query, db_conn, records, original_ids):
-    try:
-        # sanitize input if input is a string
-        for record in records:
-            for i, val in enumerate(record):
-                if isinstance(val, str):
-                    record[i] = sanitize_string(val)
+    sanitized_records = sanitize_tuples(records)
 
-        await db_conn.executemany(insert_query, records, timeout=int(PG_TIMEOUT))
+    try:
+        await db_conn.executemany(insert_query, sanitized_records, timeout=int(PG_TIMEOUT))
     except Exception as err:
         print('Batch insert into postgres ERROR:', err)
         # excute insert query one by one if batch insert failed
-        for i, record in enumerate(records):
+        for i, record in enumerate(sanitized_records):
             # print original id for debugging
             print('Inserting record', original_ids[i])
             try:
@@ -268,8 +264,21 @@ async def insert_into_postgres(insert_query, db_conn, records, original_ids):
         await asyncio.sleep(float(PG_COOLDOWN_TIME))
 
 
+def sanitize_tuples(tuples):
+    sanitize_tuples = []
+    for tuple in tuples:
+        sanitize_tuple = []
+        for val in tuple:
+            sanitize_tuple.append(sanitize_string(val))
+        sanitize_tuples.append(sanitize_tuple)
+    return sanitize_tuples
+
+
 def sanitize_string(val):
-    return replace_surrogates(remove_null_bytes(val))
+    # sanitize valu if val is a string
+    if isinstance(val, str):
+        return replace_surrogates(remove_null_bytes(val))
+    return val
 
 
 def remove_null_bytes(val):