Package h-client fails to build with an error during sanity-check phase:

```
starting phase `sanity-check'
validating 'hclient' /gnu/store/spgvgl83h6z9nsk940nl5kzrbsrlh4xp-h-client-0.0a0-138/lib/python2.7/site-packages
...checking requirements: OK
...trying to load module hclient: OK
...trying to load module tests_hclient: OK
...trying to load endpoint console_scripts h-client: ERROR:
Traceback (most recent call last):
  File "/gnu/store/nwwr89v2vyg1hs48i49m083vhczsgh3m-sanity-check.py", line 85, in <module>
    ep.load()
  File "/gnu/store/y14nmmzzcs2a6m2gnn2diak2gkf5v2av-python2-2.7.18/lib/python2.7/site-packages/pkg_resources/__init__.py", line 2443, in load
    return self.resolve()
  File "/gnu/store/y14nmmzzcs2a6m2gnn2diak2gkf5v2av-python2-2.7.18/lib/python2.7/site-packages/pkg_resources/__init__.py", line 2449, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
  File "/gnu/store/spgvgl83h6z9nsk940nl5kzrbsrlh4xp-h-client-0.0a0-138/lib/python2.7/site-packages/hclient/gtkclient.py", line 24, in <module>
    import gtk
ImportError: No module named gtk
```

My system:

```
christopher@theoden ~$ neofetch --stdout
christopher@theoden 
------------------- 
OS: Guix System d422848146f4b7d6aaec20776daaac8964416a0f x86_64 
Host: OptiPlex 9020 00 
Kernel: 5.15.5-gnu 
Uptime: 13 days, 1 hour, 12 mins 
Packages: 91 (guix-system), 150 (guix-user) 
Shell: bash 5.0.16 
Resolution: 1920x1080 
DE: GNOME 
Theme: Adwaita [GTK2/3] 
Icons: Adwaita [GTK2/3] 
Terminal: .emacs-27.2-rea 
CPU: Intel i5-4570 (4) @ 3.600GHz 
GPU: Intel HD Graphics 
GPU: AMD ATI Radeon HD 8490 / R5 235X OEM 
Memory: 3356MiB / 7869MiB 
```

-- 
📛 Christopher Howard
🚀 gemini://gem.librehacker.com
🌐 https://portal.mozz.us/gemini/gem.librehacker.com

בראשית ברא אלהים את השמים ואת הארץ