diff --git a/vm/src/stdlib/os.rs b/vm/src/stdlib/os.rs
index f0550d587..b4d52fe09 100644
--- a/vm/src/stdlib/os.rs
+++ b/vm/src/stdlib/os.rs
@@ -6,6 +6,8 @@ use std::fs::OpenOptions;
 use std::io::{self, Error, ErrorKind, Read, Write};
 #[cfg(unix)]
 use std::os::unix::fs::OpenOptionsExt;
+#[cfg(windows)]
+use std::os::windows::fs::OpenOptionsExt;
 use std::time::{Duration, SystemTime};
 use std::{env, fs};
 
@@ -91,6 +93,7 @@ pub fn os_close(vm: &VirtualMachine, args: PyFuncArgs) -> PyResult {
     Ok(vm.get_none())
 }
 
+#[cfg(any(unix, windows))]
 pub fn os_open(vm: &VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(
         vm,
@@ -126,6 +129,11 @@ pub fn os_open(vm: &VirtualMachine, args: PyFuncArgs) -> PyResult {
     Ok(vm.ctx.new_int(raw_file_number(handle)))
 }
 
+#[cfg(all(not(unix), not(windows)))]
+pub fn os_open(vm: &VirtualMachine, args: PyFuncArgs) -> PyResult {
+    unimplemented!()
+}
+
 pub fn convert_io_error(vm: &VirtualMachine, err: io::Error) -> PyObjectRef {
     let os_error = match err.kind() {
         ErrorKind::NotFound => {