可以通过try/except语句来实现捕获异常，如下:
bpython version 0.15 on top of Python 3.5.1+ /usr/bin/python3
>>> x=3
>>> y=0
>>> x/y
Traceback (most recent call last):
File "<input>", line 1, in <module>
x/y
ZeroDivisionError: division by zero
捕获异常：
这里只输出提示信息：
#!/usr/bin/env python
# encoding: utf-8
"""
@author: kamil.liu @file: except.py
@time: 16-5-30 上午11:40
"""
x = 3
y = 0
try:
print(x/y)
except ZeroDivisionError:
print('The second number can`t be zero')
结果：
/usr/bin/python3.5 /home/kamil/PycharmProjects/untitled/test1/try/except.py
The second number can`t be zero Process finished with exit code 0
不加参数，捕获异常：
如果捕获到异常，不处理，只传递异常，可以调用不带参数的raise，如下事例：
传递异常：
#!/usr/bin/env python
# encoding: utf-8 class MuffledCalculator:
muffled = False
def calc(self,expr):
try:
return eval(expr)
except ZeroDivisionError:
if self.muffled:
print("Division by zero is illegal")
else:raise
calculator = MuffledCalculator()
print(calculator.calc('9/3'))
#calculator.muffled = True
print(calculator.calc('9/0')) """
/usr/bin/python3.5 /home/kamil/PycharmProjects/untitled/test1/try/except.py
3.0
Traceback (most recent call last):
File "/home/kamil/PycharmProjects/untitled/test1/try/except.py", line 16, in <module>
print(calculator.calc('9/0'))
File "/home/kamil/PycharmProjects/untitled/test1/try/except.py", line 8, in calc
return eval(expr)
File "<string>", line 1, in <module>
ZeroDivisionError: division by zero Process finished with exit code 1
"""
不传递异常
#!/usr/bin/env python
# encoding: utf-8 class MuffledCalculator:
muffled = False
def calc(self,expr):
try:
return eval(expr)
except ZeroDivisionError:
if self.muffled:
print("Division by zero is illegal")
else:raise
calculator = MuffledCalculator()
print(calculator.calc('9/3'))
calculator.muffled = True
print(calculator.calc('9/0')) """
/usr/bin/python3.5 /home/kamil/PycharmProjects/untitled/test1/try/except.py
3.0
Division by zero is illegal
None Process finished with exit code 0
"""
除0行为发生，屏蔽被打开，calc会返回None。