Package name uppercase problem with windows image

Overview

I found a strange pip problem on windows based image related to python packages that are installed with capital letters in their folder name.

The problem is happening when uninstalling a package with uppercase letters in its name, eg: PyPDF2.

I confirm Linux images don't have this problem.

How to reproduce

Here are minimal reproducible steps:

docker pull python:3.13.3-windowsservercore-ltsc2022
docker run --rm -it python:3.13.3-windowsservercore-ltsc2022 powershell

# First install
pip install PyPDF2
python -c "import PyPDF2 as p; print(p.__file__)"

# Prints:
C:\Python\Lib\site-packages\PyPDF2\__init__.py

pip uninstall -y PyPDF2

# 2nd install
pip install PyPDF2
python -c "import PyPDF2 as p; print(p.__file__)"

# Prints:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
    import PyPDF2 as p; print(p.__file__)
    ^^^^^^^^^^^^^^^^^^
ModuleNotFoundError: No module named 'PyPDF2'

# Let's try lowercase:

python -c "import pypdf2 as p; print(p.__file__)"

# Prints:

C:\Python\Lib\site-packages\pypdf2\__init__.py

# Even if:
pip freeze

# Prints:
PyPDF2==3.0.1

首先在 python:3.13.3-windowsservercore-ltsc2022 镜像中复现报告的操作序列：安装 PyPDF2，卸载它，重新安装它，并比较导入路径。检查 Windows 镜像在 pip uninstall 和 site-packages 方面的行为；当包含大写字母的包能够被卸载并重新安装，同时仍可使用其预期名称导入时，即表示完成。