import matplotlib.pyplot as plt                                                                         
import mpl_toolkits.mplot3d.axes3d as axes3d                                                            
import numpy as np                                                                                      
                                                                                                        
def plot_sphere():                                                                                      
                                                                                                        
    # Spherical grid.                                                                                   
    th = np.linspace(0., np.pi, 100)                                                                    
    ph = np.linspace(0., 2. * np.pi, 300)                                                               
    theta, phi = np.meshgrid(th, ph)                                                                    
                                                                                                        
    # Plot sphere.                                                                                      
    x_sphere = np.sin(theta) * np.cos(phi)                                                              
    y_sphere = np.sin(theta) * np.sin(phi)                                                              
    z_sphere = np.cos(theta)                                                                            
                                                                                                        
    fig = plt.figure()                                                                                  
    ax = fig.add_subplot(1, 1, 1, projection='3d')                                                      
    ax.plot_surface(x_sphere, y_sphere, z_sphere, color='blue')                                         
    plt.savefig("Test.pdf", bbox_inches="tight")                                                        
    plt.close(fig)                                                                                      
                                                                                                        
                                                                                                        
def run():                                                                                              
    plot_sphere()                                                                                       
                                                                                                        
                                                                                                        
run()