code: def _get_fill(arr: ABCSparseArray) -> np.ndarray:
      
      try:
          return np.asarray(arr.fill_value, dtype=arr.dtype.subtype)
      except ValueError:
          return np.asarray(arr.fill_value)
docs: Create a 0-dim ndarray containing the fill value
  
      Parameters
      ----------
      arr : SparseArray
  
      Returns
      -------
      fill_value : ndarray
          0-dim ndarray with just the fill value.
  
      Notes
      -----
      coerce fill_value to arr dtype if possible
      int64 SparseArray can have NaN as fill_value if there is no missing