Why can't download from git?

Question

linux

Good afternoon. Here I ran into a problem - I want to download the library from github, but to no avail. I enter:

pip3 install git+https://github.com/vmware/vsphere-automation-sdk-python.git

Gives me this error:

Collecting git+https://github.com/vmware/vsphere-automation-sdk-python.git
  Cloning https://github.com/vmware/vsphere-automation-sdk-python.git to /tmp/pip-req-build-w3rna8wf
  Running command git clone -q https://github.com/vmware/vsphere-automation-sdk-python.git /tmp/pip-req-build-w3rna8wf
  fatal: «https://github.com/vmware/vsphere-automation-sdk-python.git/» недоступно: gnutls_handshake() failed: An unexpected TLS packet was received.
ERROR: Command errored out with exit status 128: git clone -q https://github.com/vmware/vsphere-automation-sdk-python.git /tmp/pip-req-build-w3rna8wf Check the logs for full command output.

What is it connected with? I am using a proxy and I have a hunch that this is the problem. In general, how can this be fixed? Thanks in advance.