boolean fix

Author: Евгений Блинов

suby/proxy_module.py

@@ -33,7 +33,7 @@ def __call__(
         """
         About reading from strout and stderr: https://stackoverflow.com/a/28319191/14522393
         """
-        if platform.system() == 'Windows' and not split:
+        if platform.system() == 'Windows' and split:
             raise OSError('Windows arguments should be splitted.')  # pragma: no cover
 
         if timeout is not None and isinstance(token, DefaultToken):