diff --git a/vm/src/obj/objbool.rs b/vm/src/obj/objbool.rs
index 3a97312cd..fc5b57658 100644
--- a/vm/src/obj/objbool.rs
+++ b/vm/src/obj/objbool.rs
@@ -3,7 +3,7 @@ use num_traits::Zero;
 
 use crate::function::PyFuncArgs;
 use crate::pyobject::{
-    IntoPyObject, PyContext, PyObjectRef, PyResult, TryFromObject, TypeProtocol,
+    IdProtocol, IntoPyObject, PyContext, PyObjectRef, PyResult, TryFromObject, TypeProtocol,
 };
 use crate::vm::VirtualMachine;
 
@@ -29,6 +29,12 @@ impl TryFromObject for bool {
 
 /// Convert Python bool into Rust bool.
 pub fn boolval(vm: &VirtualMachine, obj: PyObjectRef) -> PyResult<bool> {
+    if obj.is(&vm.ctx.true_value) {
+        return Ok(true);
+    }
+    if obj.is(&vm.ctx.false_value) {
+        return Ok(false);
+    }
     let rs_bool = match vm.get_method(obj.clone(), "__bool__") {
         Some(method_or_err) => {
             // If descriptor returns Error, propagate it further
diff --git a/vm/src/vm.rs b/vm/src/vm.rs
index 635418a28..c79323094 100644
--- a/vm/src/vm.rs
+++ b/vm/src/vm.rs
@@ -449,8 +449,12 @@ impl VirtualMachine {
 
     // Container of the virtual machine state:
     pub fn to_str(&self, obj: &PyObjectRef) -> PyResult<PyStringRef> {
-        let str = self.call_method(&obj, "__str__", vec![])?;
-        TryFromObject::try_from_object(self, str)
+        if obj.class().is(&self.ctx.types.str_type) {
+            Ok(obj.clone().downcast().unwrap())
+        } else {
+            let s = self.call_method(&obj, "__str__", vec![])?;
+            PyStringRef::try_from_object(self, s)
+        }
     }
 
     pub fn to_pystr<'a, T: Into<&'a PyObjectRef>>(&'a self, obj: T) -> PyResult<String> {