code: def astype(self, dtype, copy=True):
          
  
          # if we are astyping to an existing IntegerDtype we can fastpath
          if isinstance(dtype, _IntegerDtype):
              result = self._data.astype(dtype.numpy_dtype, copy=False)
              return type(self)(result, mask=self._mask, copy=False)
  
          # coerce
          data = self._coerce_to_ndarray()
          return astype_nansafe(data, dtype, copy=None)
docs: Cast to a NumPy array or IntegerArray with 'dtype'.
  
          Parameters
          ----------
          dtype : str or dtype
              Typecode or data-type to which the array is cast.
          copy : bool, default True
              Whether to copy the data, even if not necessary. If False,
              a copy is made only if the old dtype does not match the
              new dtype.
  
          Returns
          -------
          array : ndarray or IntegerArray
              NumPy ndarray or IntergerArray with 'dtype' for its dtype.
  
          Raises
          ------
          TypeError
              if incompatible type with an IntegerDtype, equivalent of same_kind
              casting