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+```mermaid
+  graph TD;
+      A-->B;
+      A-->C;
+      B-->D;
+      C-->D;
+```
+
+```mermaid
+    stateDiagram
+    [*] --> Active
+
+    state Active {
+        [*] --> NumLockOff
+        NumLockOff --> NumLockOn : EvNumLockPressed
+        NumLockOn --> NumLockOff : EvNumLockPressed
+    }
+```