Add proxies arg to TM1Service

[MariusWirtz]

Accept proxies argument in TM1Service constructor

@Cubewise-gtejeda
please upgrade to this branch and test it.

pip uninstall tm1py
pip install https://github.com/cubewise-code/tm1py/archive/refs/heads/feature/support-proxy.zip

proxies = {
   'http': 'http://proxy.example.com:8080',
   'https': 'http://secureproxy.example.com:8090',
}

with TM1Service(**params, proxies=proxies) as tm1:
    print(tm1.server.get_product_version())
}

[MariusWirtz]

@Cubewise-gtejeda please try again.

Now we pass the proxies to the requests Session object before the first request is made to TM1.

[Cubewise-gtejeda]

Package containing module 'urllib3' is not listed in the project requirements
PyCharm shows this message on line 13

[Cubewise-gtejeda]

Proxies are configured in the config.ini file as such:
proxies={{"http":"http://192.168.0.10:3128"},{"https":"http://192.168.0.10:3128"}}

Still getting this error:
ValueError: No response returned from URL: 'https://cubewise.planning-analytics.ibmcloud.com/tm1/api/plansamp/api/v1/Configuration/ProductVersion/$value'. Please double check your address and port number in the URL.

Last entry in the trace:
TM1py\Services\RestService.py:252: in connect
self._start_session(...

[Cubewise-gtejeda]

Line 191:
self._proxies = kwargs.get('proxies', None)
This is setting the value correctly.

Line 228:

        self._s = Session()
        if self._proxies:
            self._s.proxies = self._proxies

This also gets populated correctly.

[Cubewise-gtejeda]

In sessions.py from the requests package line 575:
proxies = proxies or {}

proxies is empty.

[Cubewise-gtejeda]

When setting environment variables it works:

import os
os.environ["HTTP_PROXY"] = "http://192.168.0.10:3128"
os.environ["HTTPS_PROXY"] = "http://192.168.0.10:3128"

Even through the proxies in sessions.py in the requests package remains empty.
See: https://requests.readthedocs.io/en/latest/user/advanced/#proxies

[Cubewise-gtejeda]

Correction from #911 (comment):
The proxies in the configuration file should be specified as below:
proxies={"http":"http://192.168.0.10:3128","https":"http://192.168.0.10:3128"}