package grub-efi-amd64 2.02~beta2-36ubuntu3.10 failed to install/upgrade: subprocess installed post-installation script returned error exit status 2

[DonKaron]

update > upgrade > reinstalling grub did not solve this

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: grub-efi-amd64 2.02~beta2-36ubuntu3.10
ProcVersionSignature: Ubuntu 4.4.0-79.100-generic 4.4.67
Uname: Linux 4.4.0-79-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia
ApportVersion: 2.20.1-0ubuntu2.6
Architecture: amd64
Date: Sat May 20 07:19:17 2017
DuplicateSignature:
 package:grub-efi-amd64:2.02~beta2-36ubuntu3.10
 Setting up grub-efi-amd64 (2.02~beta2-36ubuntu3.10) ...
 /var/lib/dpkg/info/grub-efi-amd64.postinst: line 703: syntax error near unexpected token `fi'
 dpkg: error processing package grub-efi-amd64 (--configure):
  subprocess installed post-installation script returned error exit status 2
ErrorMessage: subprocess installed post-installation script returned error exit status 2
InstallationDate: Installed on 2017-01-08 (132 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Beta amd64 (20170108)
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-79-generic root=UUID=5c6a0269-0e8c-4872-bfb9-c2561b695721 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.2
 apt 1.2.21
SourcePackage: grub2
Title: package grub-efi-amd64 2.02~beta2-36ubuntu3.10 failed to install/upgrade: subprocess installed post-installation script returned error exit status 2
UpgradeStatus: No upgrade log present (probably fresh install)

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make this software better. This particular crash has already been reported and is a duplicate of bug #1692175, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.