remove unnecessary condition

Author: TomAugspurger

pandas/core/arrays/datetimelike.py

@@ -25,7 +25,6 @@
     is_list_like, is_object_dtype, is_offsetlike, is_period_dtype,
     is_string_dtype, is_timedelta64_dtype, is_unsigned_integer_dtype,
     needs_i8_conversion, pandas_dtype)
-from pandas.core.dtypes.dtypes import DatetimeTZDtype
 from pandas.core.dtypes.generic import ABCDataFrame, ABCIndexClass, ABCSeries
 from pandas.core.dtypes.inference import is_array_like
 from pandas.core.dtypes.missing import isna
@@ -1177,8 +1176,6 @@ def _time_shift(self, periods, freq=None):
                 freq = frequencies.to_offset(freq)
             offset = periods * freq
             result = self + offset
-            if getattr(self, 'tz', None):
-                result._dtype = DatetimeTZDtype(tz=self.tz)
             return result
 
         if periods == 0: