How to use circles in Python.

In Python, you can draw circles using the turtle module or the matplotlib library.

Here is an example code using the turtle module to draw a circle.

import turtle

# 创建画布和画笔
canvas = turtle.Screen()
pen = turtle.Turtle()

# 设置画笔的形状和颜色
pen.shape("turtle")
pen.color("green")

# 绘制圆形
radius = 100
pen.circle(radius)

# 关闭画布
canvas.exitonclick()

The example code below shows how to draw a circle using the matplotlib library.

import matplotlib.pyplot as plt

# 创建一个figure对象和一个坐标系对象
fig, ax = plt.subplots()

# 绘制圆形
circle = plt.Circle((0, 0), radius=1, color="green", alpha=0.5)
ax.add_patch(circle)

# 设置坐标系的范围
ax.set_xlim(-1.5, 1.5)
ax.set_ylim(-1.5, 1.5)

# 显示图形
plt.show()

The code above uses both the turtle module and the matplotlib library to draw circles. You can choose one of these methods based on your needs to draw a circle.