Problem with apt-get before upgrading to Python 3.7

This problem ocurrs before upgrating to Python 3.7 and setted by default python3 command and pc Restarted, don't work reinstall python3-apt to solve this.

Ubuntu version: Ubuntu 18.04.2 TLS

if you try to execute the terminal didn't work, but with XTerm can you try:

sudo apt-get update

The result:

Hit:1 https://repo.skype.com/deb stable InRelease
Hit:2 http://co.archive.ubuntu.com/ubuntu bionic InRelease
Ign:3 http://dl.google.com/linux/chrome/deb stable InRelease
Get:4 http://co.archive.ubuntu.com/ubuntu bionic-updates InRelease [88,7 kB]
Hit:5 https://download.mono-project.com/repo/ubuntu vs-bionic InRelease
Get:6 http://security.ubuntu.com/ubuntu bionic-security InRelease [88,7 kB]
Hit:7 https://download.sublimetext.com apt/stable/ InRelease
Get:8 http://co.archive.ubuntu.com/ubuntu bionic-backports InRelease [74,6 kB]
Hit:9 http://dl.google.com/linux/chrome/deb stable Release
Fetched 252 kB in 1s (212 kB/s)
Traceback (most recent call last):
  File "/usr/lib/cnf-update-db", line 8, in <module>
    from CommandNotFound.db.creator import DbCreator
  File "/usr/lib/python3/dist-packages/CommandNotFound/db/creator.py", line 11, in <module>
    import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'
Error in sys.excepthook:
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/apport_python_hook.py", line 63, in apport_excepthook
    from apport.fileutils import likely_packaged, get_recent_crashes
  File "/usr/lib/python3/dist-packages/apport/__init__.py", line 5, in <module>
    from apport.report import Report
  File "/usr/lib/python3/dist-packages/apport/report.py", line 30, in <module>
    import apport.fileutils
  File "/usr/lib/python3/dist-packages/apport/fileutils.py", line 23, in <module>
    from apport.packaging_impl import impl as packaging
  File "/usr/lib/python3/dist-packages/apport/packaging_impl.py", line 24, in <module>
    import apt
  File "/usr/lib/python3/dist-packages/apt/__init__.py", line 23, in <module>
    import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'

Original exception was:
Traceback (most recent call last):
  File "/usr/lib/cnf-update-db", line 8, in <module>
    from CommandNotFound.db.creator import DbCreator
  File "/usr/lib/python3/dist-packages/CommandNotFound/db/creator.py", line 11, in <module>
    import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'
Reading package lists... Done
E: Problem executing scripts APT::Update::Post-Invoke-Success 'if /usr/bin/test -w /var/lib/command-not-found/ -a -e /usr/lib/cnf-update-db; then /usr/lib/cnf-update-db > /dev/null; fi'
E: Sub-process returned an error code