code: def _insert_file(cursor, file, media_type):
      
      resource_hash = _get_file_sha1(file)
      cursor.execute("SELECT fileid FROM files WHERE sha1 = %s",
                     (resource_hash,))
      try:
          fileid = cursor.fetchone()[0]
      except (IndexError, TypeError):
          cursor.execute("INSERT INTO files (file, media_type) "
                         "VALUES (%s, %s)"
                         "RETURNING fileid",
                         (psycopg2.Binary(file.read()), media_type,))
          fileid = cursor.fetchone()[0]
      return fileid, resource_hash
docs: Upsert the ``file`` and ``media_type`` into the files table.
      Returns the ``fileid`` and ``sha1`` of the upserted file.