simplified concatenating mulitple dataframes into one

sensospot_data/parser.py

@@ -107,9 +107,7 @@ def parse_multiple_files(file_list):
         raise ValueError("Empty file list provided")
     collection = (_silenced_parse_file(path) for path in file_list)
     filtered = (frame for frame in collection if frame is not None)
-    data_frame = next(filtered)
-    for next_frame in filtered:
-        data_frame = data_frame.append(next_frame, ignore_index=True)
+    data_frame = pandas.concat(filtered, ignore_index=True).reset_index()
     data_frame[META_DATA_WELL_ROW] = data_frame[META_DATA_WELL_ROW].astype(
         "category"
     )