已安装flask_Humanify模块但运行Python代码时提示ModuleNotFoundError的问题求助

大家好，我遇到了一个百思不得其解的问题，希望能得到社区朋友们的帮助：

我通过/usr/local/bin/python3.6 -m pip install flask_Humanify命令安装了flask_Humanify模块，安装过程的输出显示模块已经成功安装在/usr/local/lib/python3.6/site-packages目录下。但当我用同一个Python解释器/usr/local/bin/python3.6 test.py运行我的代码时，却抛出了如下错误：

Traceback (most recent call last):
  File "once.py", line 29, in <module>
    from flask_Humanify import Humanify
ModuleNotFoundError: No module named 'flask_Humanify'

为了排查问题，我已经做了以下验证：

• 确认Python解释器版本：

  /usr/local/bin/python3.6 --version
  # 输出结果：
  Python 3.6.3
  

• 确认pip与Python解释器的关联：

  /usr/local/bin/python3.6 -m pip --version
  # 输出结果：
  pip 21.3.1 from /usr/local/lib/python3.6/site-packages/pip (python 3.6)
  

• 查看已安装模块列表，确实能找到flask-Humanify：

  pip list -v
  # 其中相关行：
  flask-Humanify 0.2.3 /usr/local/lib/python3.6/site-packages pip
  

• 重新执行安装命令，输出显示模块已存在：

  /usr/local/bin/python3.6 -m pip install flask_Humanify
  

  Requirement already satisfied: flask_Humanify in /usr/local/lib/python3.6/site-packages (0.2.3)
  Requirement already satisfied: cryptography in /usr/local/lib/python3.6/site-packages (from flask_Humanify) (40.0.2)
  Requirement already satisfied: opencv-python-headless in /usr/local/lib/python3.6/site-packages (from flask_Humanify) (4.5.5.64)
  Requirement already satisfied: numpy in /usr/local/lib/python3.6/site-packages (from flask_Humanify) (1.17.4)
  Requirement already satisfied: pydub in /usr/local/lib/python3.6/site-packages (from flask_Humanify) (0.25.1)
  Requirement already satisfied: Flask in /usr/local/lib/python3.6/site-packages (from flask_Humanify) (1.1.1)
  Requirement already satisfied: netaddr in /usr/local/lib/python3.6/site-packages (from flask_Humanify) (0.10.1)
  Requirement already satisfied: scipy in /usr/local/lib/python3.6/site-packages (from flask_Humanify) (1.3.3)
  Requirement already satisfied: cffi>=1.12 in /usr/local/lib/python3.6/site-packages (from cryptography->flask_Humanify) (1.15.1)
  Requirement already satisfied: Jinja2>=2.10.1 in /usr/local/lib/python3.6/site-packages (from Flask->flask_Humanify) (2.10.3)
  Requirement already satisfied: Werkzeug>=0.15 in /usr/local/lib/python3.6/site-packages (from Flask->flask_Humanify) (0.16.0)
  Requirement already satisfied: click>=5.1 in /usr/local/lib/python3.6/site-packages (from Flask->flask_Humanify) (7.0)
  Requirement already satisfied: itsdangerous>=0.24 in /usr/local/lib/python3.6/site-packages (from Flask->flask_Humanify) (1.1.0)
  Requirement already satisfied: importlib-resources in /usr/local/lib/python3.6/site-packages (from netaddr->flask_Humanify) (5.4.0)
  Requirement already satisfied: pycparser in /usr/local/lib/python3.6/site-packages (from cffi>=1.12->cryptography->flask_Humanify) (2.21)
  Requirement already satisfied: MarkupSafe>=0.23 in /usr/local/lib/python3.6/site-packages (from Jinja2>=2.10.1->Flask->flask_Humanify) (1.1.1)
  Requirement already satisfied: zipp>=3.1.0 in /usr/local/lib/python3.6/site-packages (from importlib-resources->netaddr->flask_Humanify) (3.6.0)
  WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv

我实在想不通，明明用的是同一个Python解释器，模块也确实在对应的site-packages目录里，为什么运行代码时就是找不到这个模块呢？有没有朋友遇到过类似的问题，或者能给我一些进一步排查的方向？

内容来源于stack exchange