diff --git a/tmuxp/pane.py b/tmuxp/pane.py
index 5186d57026..1dd405b7c5 100644
--- a/tmuxp/pane.py
+++ b/tmuxp/pane.py
@@ -67,7 +67,7 @@ def tmux(self, cmd, *args, **kwargs):
         :rtype: :class:`Server.tmux`
 
         """
-        if not len([arg for arg in args if '-t' in arg]):
+        if not any(arg.startswith('-t') for arg in args):
             args = ('-t', self.get('pane_id')) + args
 
         return self.server.tmux(cmd, *args, **kwargs)
diff --git a/tmuxp/window.py b/tmuxp/window.py
index 93439d6edd..342560b1ab 100644
--- a/tmuxp/window.py
+++ b/tmuxp/window.py
@@ -76,7 +76,7 @@ def tmux(self, cmd, *args, **kwargs):
         :rtype: :class:`Server.tmux`
 
         """
-        if not len([arg for arg in args if '-t' in str(arg)]):
+        if not any(arg.startswith('-t') for arg in args):
             args = ('-t', self.get('window_id')) + args
 
         return self.server.tmux(cmd, *args, **kwargs)