How to default to default package if index-url is not avaliable?

[flamecopper]

Description

[global]
trusted-host = pypi.python.org pypi.org files.pythonhosted.org
cert = ~/.pip/cacert.cer
index-url = https:/xxxx@artifactory.trusted.xxx.com/api/pypi/pypi-remote/simple
extra-index-url = https://xxx@artifactory.trusted.xxx.com/api/pypi/visacommonssecurity-pypi-virtual/simple

Expected behavior

Hi there,
When I do a pip install it alawys goes to the index-url - this needs to connect to VPN.
How does it make it go to pypi.python.org pypi.org files.pythonhosted.org when this is a not available?

pip version

24.0.0

Python version

3.10

OS

Ubuntu

How to Reproduce

as above

Output

No response

Code of Conduct

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