copy overlay_df resolves modifying original label df in overlay init #…

…953

avoid modifying original overlay_df object passed to Overlay.__init__()

opensoundscape/preprocess/actions.py

@@ -8,6 +8,7 @@
 See the preprocessor module and Preprocessing tutorial
 for details on how to use and create your own actions.
 """
+
 import random
 import warnings
 import numpy as np
@@ -506,7 +507,7 @@ def __init__(self, is_augmentation=True, **kwargs):
 
         self.returns_labels = True
 
-        overlay_df = kwargs["overlay_df"]
+        overlay_df = kwargs["overlay_df"].copy()  # copy to avoid modifying original
         overlay_df = overlay_df[~overlay_df.index.duplicated()]  # remove duplicates
 
         # warn the user if using "different" as overlay_class