def astype(self, dtype, copy=True):
<EOL>if isinstance(dtype, _IntegerDtype):<EOL><INDENT>result = self._data.astype(dtype.numpy_dtype, copy=False)<EOL>return type(self)(result, mask=self._mask, copy=False)<EOL><DEDENT>data = self._coerce_to_ndarray()<EOL>return astype_nansafe(data, dtype, copy=None)<EOL>
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