Changing lib.pyx to highlight an issue with astype_unicode (not a fix)

Author: ThibTrip

pandas/_libs/lib.pyx

@@ -577,6 +577,8 @@ def astype_unicode(arr: ndarray, skipna: bool=False) -> ndarray[object]:
     for i in range(n):
         arr_i = arr[i]
 
+        print(f'{arr_i} is null? {checknull(arr_i)}')
+
         if not (skipna and checknull(arr_i)):
             arr_i = unicode(arr_i)