refactor[ux]: remove deprecated VyperNode properties (#3999)

This commit removes the `n` property from `Num` vyper node and the `s`
property from `Str` vyper node as they have been deprecated in the
python AST (and it is clearer to use the `value` property anyways)

vyper/ast/nodes.py

@@ -788,11 +788,6 @@ class Num(Constant):
     # inherited class for all numeric constant node types
     __slots__ = ()
 
-    @property
-    def n(self):
-        # TODO phase out use of Num.n and remove this
-        return self.value
-
     def validate(self):
         if self.value < SizeLimits.MIN_INT256:
             raise OverflowException("Value is below lower bound for all numeric types", self)
@@ -894,11 +889,6 @@ def validate(self):
             if ord(c) >= 256:
                 raise InvalidLiteral(f"'{c}' is not an allowed string literal character", self)
 
-    @property
-    def s(self):
-        # TODO phase out use of Str.s and remove this
-        return self.value
-
 
 class Bytes(Constant):
     __slots__ = ()

vyper/codegen/expr.py

@@ -89,7 +89,7 @@ def __init__(self, node, context, is_stmt=False):
 
     def parse_Int(self):
         typ = self.expr._metadata["type"]
-        return IRnode.from_list(self.expr.n, typ=typ)
+        return IRnode.from_list(self.expr.value, typ=typ)
 
     def parse_Decimal(self):
         val = self.expr.value * DECIMAL_DIVISOR
@@ -133,8 +133,8 @@ def parse_Str(self):
 
     # Byte literals
     def parse_Bytes(self):
-        bytez = self.expr.s
-        bytez_length = len(self.expr.s)
+        bytez = self.expr.value
+        bytez_length = len(self.expr.value)
         typ = BytesT(bytez_length)
         return self._make_bytelike(typ, bytez, bytez_length)
 
@@ -345,7 +345,7 @@ def parse_Subscript(self):
         elif is_tuple_like(sub.typ):
             # should we annotate expr.slice in the frontend with the
             # folded value instead of calling reduced() here?
-            index = self.expr.slice.reduced().n
+            index = self.expr.slice.reduced().value
             # note: this check should also happen in get_element_ptr
             if not 0 <= index < len(sub.typ.member_types):
                 raise TypeCheckFailure("unreachable")