Add `plt.close()` to save memory.

app.py

@@ -32,6 +32,7 @@ def classify(num: int):
     samples_df['Predict'] = y_pred
     bar = plot_bar(y_pred.value_counts())
     cm = plot_confusion_matrix(y_pred, y)
+    plt.close()
     return samples_df, bar, cm