diff --git a/tests/test_class_basics.rs b/tests/test_class_basics.rs
index 910d1eb5899..5f63ccefa82 100644
--- a/tests/test_class_basics.rs
+++ b/tests/test_class_basics.rs
@@ -245,8 +245,10 @@ fn panic_unsendable_child() {
     test_unsendable::<UnsendableChild>().unwrap();
 }
 
-fn to_string(obj: &PyAny) -> PyResult<String> {
-    Ok(obj.str()?.to_str()?.to_string())
+fn get_length(obj: &PyAny) -> PyResult<usize> {
+    let length = obj.len()?;
+
+    Ok(length)
 }
 
 #[pyclass]
@@ -254,16 +256,16 @@ struct ClassWithFromPyWithMethods {}
 
 #[pymethods]
 impl ClassWithFromPyWithMethods {
-    fn instance_method(&self, #[pyo3(from_py_with = "to_string")] argument: String) -> String {
+    fn instance_method(&self, #[pyo3(from_py_with = "get_length")] argument: usize) -> usize {
         argument
     }
     #[classmethod]
-    fn classmethod(_cls: &PyType, #[pyo3(from_py_with = "to_string")] argument: String) -> String {
+    fn classmethod(_cls: &PyType, #[pyo3(from_py_with = "get_length")] argument: usize) -> usize {
         argument
     }
 
     #[staticmethod]
-    fn staticmethod(#[pyo3(from_py_with = "to_string")] argument: String) -> String {
+    fn staticmethod(#[pyo3(from_py_with = "get_length")] argument: usize) -> usize {
         argument
     }
 }
@@ -277,11 +279,11 @@ fn test_pymethods_from_py_with() {
             py,
             instance,
             r#"
-        arg = {1: 1}
+        arg = {1: 1, 2: 3}
 
-        assert instance.instance_method(arg) == '{1: 1}'
-        assert instance.classmethod(arg) == '{1: 1}'
-        assert instance.staticmethod(arg) == '{1: 1}'
+        assert instance.instance_method(arg) == 2
+        assert instance.classmethod(arg) == 2
+        assert instance.staticmethod(arg) == 2
         "#
         );
     })
diff --git a/tests/test_pyfunction.rs b/tests/test_pyfunction.rs
index 5602b037584..b59e6e932c4 100644
--- a/tests/test_pyfunction.rs
+++ b/tests/test_pyfunction.rs
@@ -113,7 +113,7 @@ fn test_functions_with_function_args() {
 
 #[cfg(not(Py_LIMITED_API))]
 fn datetime_to_timestamp(dt: &PyAny) -> PyResult<i64> {
-    let dt: &PyDateTime = dt.extract();
+    let dt: &PyDateTime = dt.extract()?;
     let ts: f64 = dt.call_method0("timestamp")?.extract()?;
 
     Ok(ts as i64)