def is_categorical_dtype(arr_or_dtype):
if arr_or_dtype is None:<EOL><INDENT>return False<EOL><DEDENT>return CategoricalDtype.is_dtype(arr_or_dtype)<EOL>
Check whether an array-like or dtype is of the Categorical dtype.

Parameters
----------
arr_or_dtype : array-like
    The array-like or dtype to check.

Returns
-------
boolean
    Whether or not the array-like or dtype is of the Categorical dtype.

Examples
--------
>>> is_categorical_dtype(object)
False
>>> is_categorical_dtype(CategoricalDtype())
True
>>> is_categorical_dtype([1, 2, 3])
False
>>> is_categorical_dtype(pd.Categorical([1, 2, 3]))
True
>>> is_categorical_dtype(pd.CategoricalIndex([1, 2, 3]))
True