极坐标绘图

def solve():
    import matplotlib.pyplot as plt
    import numpy as np
    theta = np.linspace(____, ____*np.pi, ____)
    r = ____ + np.cos(____)
    fig = plt.figure(figsize=(____, ____))
    ax = fig.add_subplot(____, projection='____')
    ax.plot(____)
    ax.set_title(____)
    plt.show()