Using nexus 3 I configured a proxy python repository using "<https://pypi.org>" as remote storage. The url of the repository is "<http://localhost:8081/repository/pypi/>". 

Then i used `pip` to install packages using nexus repository, in `$HOME/.config/pip/pip.conf` I have the following configurations: 

```
[global]
index = http://localhost:8081/repository/pypi/pypi
index-url = http://localhost:8081/repository/pypi/stable
trusted-host = localhost

```

Now when I run `pip search pexpect` it works fine : 

```
User for localhost:8081: someuser
Password: 
pexpect (4.7.0)                  - Pexpect allows easy control of interactive console applications.
pexpect-serial (0.0.4)           - pexpect with pyseriat
...

```

But when I run `pip install pexpect` I get the following error : 

```
Collecting pexpect
User for localhost:8081: someuser
Password: 
  Could not find a version that satisfies the requirement pexpect (from versions: )
No matching distribution found for pexpect

```

Do I need extras configurations in `pip.conf` or inside my `nexus` repository ?