python无法导入模块

我有个问题.我想使用docker-py(0.4.0)库,但我无法导入它.我的代码如下:

docker.py

import docker

c = docker.Client()

c.info()

然后我收到此错误消息:

Traceback (most recent call last):
  File "./docker.py", line 1, in 
    import docker
File "/home/vagrant/docker.py", line 3, in 
  c = docker.Client()
AttributeError: 'module' object has no attribute 'Client'

当我从python解释器运行它时它工作

>>> import docker
>>> c = docker.Client()
>>> c.info()
{u'KernelVersion': u'3.13.0-35-generic', u'NFd': 12, u'MemoryLimit': 1, 
u'InitSha1': u'',u'SwapLimit': 0, u'Driver': u'devicemapper', 
u'IndexServerAddress': u'https://index.docker.io/v1/', u'NGoroutines': 11, 
u'Images': 310, u'InitPath': u'/usr/bin/docker', u'Containers': 1, 
u'ExecutionDriver': u'native-0.2', u'Debug': 0, u'NEventsListener': 0, 
u'DriverStatus': [[u'Pool Name', u'docker-8:1-140095-pool'], 
[u'Pool Blocksize', u'64 Kb'], [u'Data file', /var/lib/docker/devicemapper/devicemapper/data'], [u'Metadata file', u'/var/lib/docker/devicemapper/devicemapper/metadata'], 
[u'Data Space Used', u'3602.1 Mb'], [u'Data Space Total', u'102400.0 Mb'], 
[u'Metadata Space Used', u'8.7 Mb'], [u'Metadata Space Total', u'2048.0 Mb']], 
u'OperatingSystem': u'Ubuntu 14.04.1 LTS', u'IPv4Forwarding': 1}
>>>

我不使用任何virtualenv,只使用系统python.我在两台机器上试过,但结果相同

有人可以解释一下我做错了什么吗？