load_global shouldn't load outermost locals.

Author: cthulahoops

tests/snippets/global_nonlocal.py

@@ -15,8 +15,11 @@ def b():
 
 def x():
     def y():
+        global a
         nonlocal b
+        assert a == 4, a
         b = 3
+    a = "no!" # a here shouldn't be seen by the global above.
     b = 2
     y()
     return b

vm/src/scope.rs

@@ -179,15 +179,6 @@ impl NameProtocol for Scope {
     #[cfg_attr(feature = "flame-it", flame("Scope"))]
     /// Load a global name.
     fn load_global(&self, vm: &VirtualMachine, name: &str) -> Option<PyObjectRef> {
-        // First, take a look in the outmost local scope (the scope at top level)
-        let last_local_dict = self.locals.iter().last();
-        if let Some(local_dict) = last_local_dict {
-            if let Some(value) = local_dict.get_item_option(name, vm).unwrap() {
-                return Some(value);
-            }
-        }
-
-        // Now, take a look at the globals or builtins.
         if let Some(value) = self.globals.get_item_option(name, vm).unwrap() {
             Some(value)
         } else {