release upgrade crashes

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Error in function: install

apt_pkg.Error: E:Could not configure 'libc6:amd64'. , E:Could not perform immediate configuration on 'libnss-nis:amd64'. Please see man 5 apt.conf under APT::Immediate-Configure for details. (2)
Error in sys.excepthook:
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/problem_report.py", line 477, in add_to_existing
    self.write(f)
  File "/usr/lib/python3/dist-packages/problem_report.py", line 430, in write
    block = f.read(1048576)
  File "/usr/lib/python3.8/codecs.py", line 322, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0x8b in position 1: invalid start byte

Original exception was:
apt_pkg.Error: E:Could not configure 'libc6:amd64'. , E:Could not perform immediate configuration on 'libnss-nis:amd64'. Please see man 5 apt.conf under APT::Immediate-Configure for details. (2)
Error in function: install

apt_pkg.Error: E:Could not perform immediate configuration on 'libffi8ubuntu1:amd64'. Please see man 5 apt.conf under APT::Immediate-Configure for details. (2)
Error in sys.excepthook:
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/problem_report.py", line 477, in add_to_existing
    self.write(f)
  File "/usr/lib/python3/dist-packages/problem_report.py", line 430, in write
    block = f.read(1048576)
  File "/usr/lib/python3.8/codecs.py", line 322, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0x8b in position 1: invalid start byte

Original exception was:
apt_pkg.Error: E:Could not perform immediate configuration on 'libffi8ubuntu1:amd64'. Please see man 5 apt.conf under APT::Immediate-Configure for details. (2)

Could not install the upgrades

The upgrade has aborted. Your system could be in an unusable state. A
recovery will run now (dpkg --configure -a).

Upgrade infeasible

The upgrade could not be completed, there were errors during the
upgrade process.

Restoring original system state

Aborting
Reading package lists... Done
Building dependency tree
Reading state information... Done

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: ubuntu-release-upgrader-core 1:20.04.28
ProcVersionSignature: Ubuntu 5.4.0-52.57-generic 5.4.65
Uname: Linux 5.4.0-52-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.10
Architecture: amd64
CasperMD5CheckResult: skip
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Sun Oct 25 15:23:34 2020
InstallationDate: Installed on 2020-09-11 (44 days ago)
InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
Symptom: release-upgrade
UpgradeStatus: Upgraded to focal on 2020-10-25 (0 days ago)
modified.conffile..etc.update-manager.release-upgrades: [modified]
mtime.conffile..etc.update-manager.release-upgrades: 2020-10-25T14:43:29.129999