Error Trying to Run Lutris After Installation

After trying to run Lutris from the terminal on Ubuntu 18.04, I get this error message:

Traceback (most recent call last):
  File "/usr/local/bin/lutris", line 4, in <module>
    __import__('pkg_resources').run_script('lutris==0.5.6', 'lutris')
  File "/usr/local/lib/python3.6/dist-packages/pkg_resources/", line 667, in run_script
    self.require(requires)[0].run_script(script_name, ns)
  File "/usr/local/lib/python3.6/dist-packages/pkg_resources/", line 1455, in run_script
pkg_resources.ResolutionError: Script 'scripts/lutris' not found in metadata at '/usr/lib/python3/dist-packages/lutris-0.5.6.egg-info'

I followed the instructions on the download page exactly. Any idea what’s wrong?