利用Pycharm断点调试Python程序的方法

#!/usr/bin/python
import numpy as np

class Network:
 def __init__(self,sizes):
 self.num_layers=len(sizes)
 self.sizes=sizes
 self.biases=[np.random.randn(y,1) for y in sizes[1:]]
 self.weights=[np.random.randn(x,y) \
   for x,y in zip(sizes[1:],sizes[:-1])]
 self.null=[]

net=Network([2,3,1])
def sigmoid(z):
 return 1.0/(1.0+np.exp(-z))