ValueError" occurred with the message "rotation must be 'vertical', 'horizontal' or a number, not 45"

When executing the code "increase, decrease = tsmc.predict_future(days = 100)", a "ValueError" occurred with the message "rotation must be 'vertical', 'horizontal' or a number, not 45".

The code has been updated as follows:

plt.legend(loc = 2, prop={'size': 10});
plt.xticks(rotation='vertical')
plt.ylabel('Predicted Stock Price (US $)');
plt.xlabel('Date'); plt.title('Predictions for %s' % self.symbol);
plt.show()

However, the same issue persists. Please debug.
[stock_2330.zip](https://github.com/facebook/prophet/files/11067990/stock_2330.zip)