Dependency issue with setuptools while using pip to install python package

Question

I'm trying to install the package hana-ml (machine learning package from SAP Hana Database). I use pip with virtual environments to manage packages.

pip install hana-ml --proxy <my_companys_proxy>

It throws the following error:

Collecting hana-ml
  Downloading hana_ml-2.19.24013100-py3-none-any.whl.metadata (13 kB)
Collecting hdbcli>=2.18.22 (from hana-ml)
  Using cached hdbcli-2.19.21-cp36-abi3-win_amd64.whl.metadata (6.3 kB)
Collecting pydotplus (from hana-ml)
  Using cached pydotplus-2.0.2.tar.gz (278 kB)
  Installing build dependencies ... error
  error: subprocess-exited-with-error

  × pip subprocess to install build dependencies did not run successfully.
  │ exit code: 1
  ╰─> [7 lines of output]
      WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', ConnectionResetError(10054, 'Eine vorhandene Verbindung wurde vom Remotehost geschlossen', None, 10054, None))': /simple/setuptools/
      WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', ConnectionResetError(10054, 'Eine vorhandene Verbindung wurde vom Remotehost geschlossen', None, 10054, None))': /simple/setuptools/
      WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', ConnectionResetError(10054, 'Eine vorhandene Verbindung wurde vom Remotehost geschlossen', None, 10054, None))': /simple/setuptools/
      WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', ConnectionResetError(10054, 'Eine vorhandene Verbindung wurde vom Remotehost geschlossen', None, 10054, None))': /simple/setuptools/
      WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', ConnectionResetError(10054, 'Eine vorhandene Verbindung wurde vom Remotehost geschlossen', None, 10054, None))': /simple/setuptools/
      ERROR: Could not find a version that satisfies the requirement setuptools>=40.8.0 (from versions: none)
      ERROR: No matching distribution found for setuptools>=40.8.0
      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
error: subprocess-exited-with-error

× pip subprocess to install build dependencies did not run successfully.
│ exit code: 1
╰─> See above for output.

note: This error originates from a subprocess, and is likely not a problem with pip.

When I check if setuptools is installed with

pip list

I get that:

Package    Version
---------- -------
pip        23.3.2
setuptools 69.0.3

So it seems to be already installed and satisfying the requested requirement.

The issue happens when it tries to install a depency. Namly the package pydotplus (it tries to install the current version 2.0.2).

Collecting pydotplus (from hana-ml)
  Using cached pydotplus-2.0.2.tar.gz (278 kB)
  Installing build dependencies ... error
  error: subprocess-exited-with-error

I tried the following things.

1. Directly trying to install pydotplus
2. Installing pydotplus in a different lower version
3. Installing within an existing virtual environment
4. Installing within a completely new virtual environment
5. Installing outside of virtual environments.
6. Everything above in different networks (homeoffice-network and office-network)

Nothing helped and nobody in my company had similar issues. Does anyone have a clue?