Make sure time.strptime only accepts strings (and document the fact like

strftime). Already didn't accept bytes but make the check earlier. This also
lifts the limitation of requiring ASCII.

Closes issue #5236. Thanks Tennessee Leeuwenburg.

Lib/_strptime.py

@@ -262,7 +262,7 @@ class TimeRE(dict):
 
     def compile(self, format):
         """Return a compiled re object for the format string."""
-        return re_compile(self.pattern(format), IGNORECASE | ASCII)
+        return re_compile(self.pattern(format), IGNORECASE)
 
 _cache_lock = _thread_allocate_lock()
 # DO NOT modify _TimeRE_cache or _regex_cache without acquiring the cache lock
@@ -294,8 +294,15 @@ def _calc_julian_from_U_or_W(year, week_of_year, day_of_week, week_starts_Mon):
 
 def _strptime(data_string, format="%a %b %d %H:%M:%S %Y"):
     """Return a time struct based on the input string and the format string."""
+
+    for index, arg in enumerate([data_string, format]):
+        if not isinstance(arg, str):
+            msg = "strptime() argument {} must be str, not {}"
+            raise TypeError(msg.format(arg, index))
+
     global _TimeRE_cache, _regex_cache
     with _cache_lock:
+
         if _getlang() != _TimeRE_cache.locale_time.lang:
             _TimeRE_cache = TimeRE()
             _regex_cache.clear()