Simplify nested iteration in window attached_pane method

Author: otherJL0

libtmux/window.py

@@ -496,12 +496,9 @@ def attached_pane(self):
         :class:`Pane`
         """
         for pane in self._panes:
-            if "pane_active" in pane:
-                # for now pane_active is a unicode
-                if pane.get("pane_active") == "1":
-                    return Pane(window=self, **pane)
-                else:
-                    continue
+            # for now pane_active is a unicode
+            if "pane_active" in pane and pane.get("pane_active") == "1":
+                return Pane(window=self, **pane)
 
         return []