Error installing confluent-kafka package from source

I downloaded the .tar.gz file from here:
confluent-kafka-1.7.0.tar.gz

When I run the install command, I get this error. What does it mean and how can I overcome it? This is on CentOS 7. My setuptools are latest-greatest. pip is version 3.

./setup.py

error in confluent-kafka setup command: ‘extras_require’ must be a dictionary whose values are strings or lists of strings containing valid project/version requirement specifiers.

Ideally I want to install confluent-kafka package on a server that’s offline, i.e. lacking online access, thus want to install via source code.

According to someone more experienced in this than I, instead of building from source you can download the appropriate wheel from: confluent-kafka · PyPI

I hope that helps,
Dave

The machine is off-line and the reason for the need to install the package off-line via source.