change np.NaN to np.nan (#82)

* change np.NaN to np.nan

Testing this threw an error using numpy 2.0, which says np.NaN has been replaced by np.nan

* change comparison to np.nan to .notna()

As recommended in #82 (review)

* Remove ununsed numpy import

src/assign_images.py

@@ -5,7 +5,6 @@
 
 import geopandas as gpd
 from loguru import logger as log
-import numpy as np
 from pandas import Series
 from requests.exceptions import HTTPError
 from tenacity import RetryError
@@ -97,7 +96,7 @@ def main(
     log.info(gdf.head())
     log.info(
         "Are There Duplicates? {}",
-        gdf[gdf["image_id"] is not None and gdf["image_id"] != np.NaN]["image_id"]
+        gdf[gdf["image_id"] is not None and gdf["image_id"].notna()]["image_id"]
         .duplicated()
         .any(),
     )