在Windows上使用pip成功安装后，Python导入matplotlib失败

在Windows 10上，我已经安装了Python 3.7.3。我想通过添加模块pip install matplotlib，它似乎可以正常工作（给出成功的结果），但是当尝试使用import matplotlib.pyplot as plt它导入库时，失败了，提示找不到指定的模块。

我已经尝试过了py -m pip install...，而且python -m pip install...似乎也没有人解决我遇到的问题。

这是我尝试安装模块的方式：

c:\Users\Michael\Documents>pip install matplotlib
Collecting matplotlib
  Using cached https://files.pythonhosted.org/packages/76/e2/f87bf36a2a460857ec9c28535e00102eb6908a727e427adc6427c5dc5453/matplotlib-3.1.0-cp37-cp37m-win32.whl
Collecting pyparsing!=2.0.4,!=2.1.2,!=2.1.6,>=2.0.1 (from matplotlib)
  Using cached https://files.pythonhosted.org/packages/dd/d9/3ec19e966301a6e25769976999bd7bbe552016f0d32b577dc9d63d2e0c49/pyparsing-2.4.0-py2.py3-none-any.whl
Collecting python-dateutil>=2.1 (from matplotlib)
  Using cached https://files.pythonhosted.org/packages/41/17/c62faccbfbd163c7f57f3844689e3a78bae1f403648a6afb1d0866d87fbb/python_dateutil-2.8.0-py2.py3-none-any.whl
Collecting kiwisolver>=1.0.1 (from matplotlib)
  Using cached https://files.pythonhosted.org/packages/20/6a/e5fff2ed776ab0cd11d7c1d5d3e5e549952464a6f1b9084b7ecbd8341352/kiwisolver-1.1.0-cp37-none-win32.whl
Requirement already satisfied: numpy>=1.11 in c:\program files (x86)\python37-32\lib\site-packages (from matplotlib) (1.16.3)
Collecting cycler>=0.10 (from matplotlib)
  Using cached https://files.pythonhosted.org/packages/f7/d2/e07d3ebb2bd7af696440ce7e754c59dd546ffe1bbe732c8ab68b9c834e61/cycler-0.10.0-py2.py3-none-any.whl
Collecting six>=1.5 (from python-dateutil>=2.1->matplotlib)
  Using cached https://files.pythonhosted.org/packages/73/fb/00a976f728d0d1fecfe898238ce23f502a721c0ac0ecfedb80e0d88c64e9/six-1.12.0-py2.py3-none-any.whl
Requirement already satisfied: setuptools in c:\program files (x86)\python37-32\lib\site-packages (from kiwisolver>=1.0.1->matplotlib) (40.8.0)
Installing collected packages: pyparsing, six, python-dateutil, kiwisolver, cycler, matplotlib
Successfully installed cycler-0.10.0 kiwisolver-1.1.0 matplotlib-3.1.0 pyparsing-2.4.0 python-dateutil-2.8.0 six-1.12.0
You are using pip version 19.0.3, however version 19.1.1 is available.
You should consider upgrading via the 'python -m pip install --upgrade pip' command.

这是我的计算机上包含python的路径：

c:\Users\Michael\Documents>path
PATH=C:\Program Files (x86)\Python37-32\Scripts\;C:\Program Files (x86)\Python37-32\;....

这是我收到的错误（从python启动后从空闲或CMD）：

>>> import matplotlib.pyplot as plt
Traceback (most recent call last):
  File "<pyshell#61>", line 1, in <module>
    import matplotlib.pyplot as plt
  File "C:\Program Files (x86)\Python37-32\lib\site-packages\matplotlib\__init__.py", line 200, in <module>
    _check_versions()
  File "C:\Program Files (x86)\Python37-32\lib\site-packages\matplotlib\__init__.py", line 194, in _check_versions
    module = importlib.import_module(modname)
  File "C:\Program Files (x86)\Python37-32\lib\importlib\__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
ImportError: DLL load failed: The specified module could not be found.