Delete fastparse2.py (#13251)

We don't need it anymore as mypy now fails unconditionally if Python 2 version is selected.

Ref #12237

Co-authored-by: Ivan Levkivskyi <[email protected]>

Author: ilevkivskyi

mypy/fastparse.py

@@ -1821,15 +1821,6 @@ def note(self, msg: str, line: int, column: int) -> None:
     def translate_expr_list(self, l: Sequence[ast3.expr]) -> List[Type]:
         return [self.visit(e) for e in l]
 
-    def visit_raw_str(self, s: str) -> Type:
-        # An escape hatch that allows the AST walker in fastparse2 to
-        # directly hook into the Python 3 type converter in some cases
-        # without needing to create an intermediary `Str` object.
-        _, typ = parse_type_comment(
-            s.strip(), self.line, -1, self.errors, self.assume_str_is_unicode
-        )
-        return typ or AnyType(TypeOfAny.from_error)
-
     def visit_Call(self, e: Call) -> Type:
         # Parse the arg constructor
         f = e.func