# dpkg -i *.deb
Selecting previously unselected package python3-mitogen.
(Reading database ... 566826 files and directories currently installed.)
Preparing to unpack python3-mitogen_0.2.8-1_all.deb ...
Unpacking python3-mitogen (0.2.8-1) ...
Setting up python3-mitogen (0.2.8-1) ...
  File "/usr/lib/python3/dist-packages/ansible_mitogen/compat/simplejson/decoder.py", line 148
    def JSONObject((s, end), encoding, strict, scan_once, object_hook, _w=WHITESPACE.match, _ws=WHITESPACE_STR):
                   ^
SyntaxError: invalid syntax

  File "/usr/lib/python3/dist-packages/ansible_mitogen/compat/simplejson/encoder.py", line 264
    False=False,
        ^
SyntaxError: invalid syntax

dpkg: error processing package python3-mitogen (--install):
 installed python3-mitogen package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
 python3-mitogen