导入matplotlib时，出现以下错误消息。如何解决这个问题？

Question

当我将matplot库导入我的代码时，出现以下dll错误

import matplotlib
matplotlib.__version__

Traceback (most recent call last):
  File "e:\FourthYear\Research\Practice\testi.py", line 1, in <module>
    import matplotlib.pyplot as plt
  File "C:\Python27\lib\site-packages\matplotlib\__init__.py", line 129, in <module>
    from matplotlib.cbook import is_string_like
  File "C:\Python27\lib\site-packages\matplotlib\cbook.py", line 28, in <module>
    import numpy as np
  File "C:\Python27\lib\site-packages\numpy\__init__.py", line 170, in <module>
    from . import add_newdocs
  File "C:\Python27\lib\site-packages\numpy\add_newdocs.py", line 13, in <module>
    from numpy.lib import add_newdoc
  File "C:\Python27\lib\site-packages\numpy\lib\__init__.py", line 8, in <module>
    from .type_check import *
  File "C:\Python27\lib\site-packages\numpy\lib\type_check.py", line 11, in <module>
    import numpy.core.numeric as _nx
  File "C:\Python27\lib\site-packages\numpy\core\__init__.py", line 6, in <module>
    from . import multiarray
ImportError: DLL load failed: %1 is not a valid Win32 application.