>>> from recommendation import critics

Traceback (most recent call last):

  File "<pyshell#7>", line 1, in <module>

    from recommendation import critics

ImportError: No module named 'recommendation'

请把目录C:\Python34\PCI_Code\chapter2\加到系统路径中，

>>> import sys

>>> sys.path.append("C:\Python34\PCI_Code\chapter2")

>>> from recommendations import critics

>>> 

或者切换到文件所在的目录中，

 

C:\Python34\PCI_Code\chapter2>python

>>> from recommendations import *

>>> 

------------------------------------------------------------------------------------------------------------------------------------
使用reload()时出现如下错误

>>> from imp import reload

>>> reload(recommendations)

Traceback (most recent call last):

  File "<pyshell#86>", line 1, in <module>

    reload(recommendations)

NameError: name 'recommendations' is not defined

原因是因为在reload某个模块的时候，需要先import来加载需要的模块，这时候再去reload就不会有问题，具体看下面代码:

>>> from imp import reload

>>> import recommendations

>>> reload(recommendations)

<module 'recommendations' from 'C:\\Python34\\PCI_Code\\chapter2\\recommendations.py'>

>>>