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

Examples
--------
>>> is_period_dtype(object)
False
>>> is_period_dtype(PeriodDtype(freq="D"))
True
>>> is_period_dtype([1, 2, 3])
False
>>> is_period_dtype(pd.Period("2017-01-01"))
False
>>> is_period_dtype(pd.PeriodIndex([], freq="A"))
True