fix: add str.isascii method

Author: ujex256

pandas/core/strings/base.py

@@ -174,6 +174,10 @@ def _str_isalnum(self):
     def _str_isalpha(self):
         pass
 
+    @abc.abstractmethod
+    def _str_isascii(self):
+        pass
+
     @abc.abstractmethod
     def _str_isdecimal(self):
         pass

pandas/core/strings/object_array.py

@@ -409,6 +409,9 @@ def _str_isalnum(self):
     def _str_isalpha(self):
         return self._str_map(str.isalpha, dtype="bool")
 
+    def _str_isascii(self):
+        return self._str_map(str.isascii, dtype="bool")
+
     def _str_isdecimal(self):
         return self._str_map(str.isdecimal, dtype="bool")