fix pypy

Author: adriangb

src/validators/union.rs

@@ -250,18 +250,10 @@ impl BuildValidator for TaggedUnionValidator {
         let mut discriminators = Vec::with_capacity(choices.len());
         let schema_choices: &PyDict = schema.get_as_req(intern!(py, "choices"))?;
         let schema_choice_keys = schema_choices.keys();
-        let discriminator_validator = LiteralValidator::build(
-            PyDict::from_sequence(
-                py,
-                vec![
-                    (intern!(py, "type"), intern!(py, "literal").as_ref()),
-                    (intern!(py, "expected"), schema_choice_keys.as_ref()),
-                ]
-                .into_py(py),
-            )?,
-            config,
-            definitions,
-        )?;
+        let discriminator_validator_schema = PyDict::new(py);
+        discriminator_validator_schema.set_item(intern!(py, "type"), intern!(py, "literal").as_ref())?;
+        discriminator_validator_schema.set_item(intern!(py, "expected"), schema_choice_keys.as_ref())?;
+        let discriminator_validator = LiteralValidator::build(discriminator_validator_schema, config, definitions)?;
         for (choice_key, choice_schema) in schema_choices.iter() {
             discriminators.push(choice_key);
             let validator = build_validator(choice_schema, config, definitions)?;