[NFC] Remove dead code for python<3.8 (#5280)

Signed-off-by: Anatoly Myachev <[email protected]>

Author: anmyachev

python/triton/compiler/code_generator.py

@@ -1,7 +1,6 @@
 import ast
 import inspect
 import re
-import sys
 import warnings
 import os
 import textwrap
@@ -1176,17 +1175,6 @@ def visit_BoolOp(self, node: ast.BoolOp):
 
     _method_name_for_bool_op: Dict[Type[ast.boolop], str] = {ast.And: 'logical_and', ast.Or: 'logical_or'}
 
-    if sys.version_info < (3, 8):
-
-        def visit_NameConstant(self, node):
-            return constexpr(node.value)
-
-        def visit_Num(self, node):
-            return constexpr(node.n)
-
-        def visit_Str(self, node):
-            return constexpr(ast.literal_eval(node))
-
     def visit_Attribute(self, node):
         lhs = self.visit(node.value)
         if _is_triton_tensor(lhs) and node.attr == "T":