add default value

vyper/builtins/functions.py

@@ -1061,23 +1061,24 @@ def fetch_call_return(self, node):
 
         kwargz = {i.arg: i.value for i in node.keywords}
 
-        delegate_call = kwargz.get("is_delegate_call")
-        static_call = kwargz.get("is_static_call")
+        delegate_call = kwargz.get("is_delegate_call", False)
+        static_call = kwargz.get("is_static_call", False)
         if delegate_call and static_call:
             raise ArgumentException(
-                "Call may use one of `is_delegate_call` or `is_static_call`, not both"
+                "Call may use one of `is_delegate_call` or `is_static_call`, not both", node
             )
 
         value = kwargz.get("value")
         if (delegate_call or static_call) and value is not None:
-            raise ArgumentException("value= may not be passed for static or delegate calls!")
+            raise ArgumentException("value= may not be passed for static or delegate calls!", node)
 
         fn_node = node.get_ancestor(vy_ast.FunctionDef)
         fn_type = fn_node._metadata["func_type"]
         if not static_call and not fn_type.is_mutable:
             raise StateAccessViolation(
                 f"Cannot make modifying calls from {fn_type.mutability},"
-                " use `is_static_call=True` to perform this action"
+                " use `is_static_call=True` to perform this action",
+                node,
             )
 
         outsize = kwargz.get("max_outsize")