如何修改代码可以将平均价格打印到图表中?

import matplotlib.pyplot as plt

# Create a list of prices
prices = [10, 12, 15, 18, 21]

# Calculate the average price
average_price = sum(prices) / len(prices)

# Create a line plot of the prices
plt.plot(prices)

# Add a label to the plot
plt.xlabel("Price")
plt.ylabel("Price")
plt.title("Price vs. Price")

# Show the plot
plt.show()

To print the average price on the chart, we can use the plt.text() function. Here's an updated code with the plt.text() function:

import matplotlib.pyplot as plt

# Create a list of prices
prices = [10, 12, 15, 18, 21]

# Calculate the average price
average_price = sum(prices) / len(prices)

# Create a line plot of the prices
plt.plot(prices)

# Add labels to the x and y axes
plt.xlabel("Price")
plt.ylabel("Price")

# Add a text label to the average price
plt.text(average_price, 15, f"Average Price: {average_price}", fontsize=12)

# Show the plot
plt.show()
```