Comment 9 for bug 1536093

I got the same and sudo dpkg -P libxapian-1.3-4 1.3.3-0ubuntu2 didn't work.
I had to manually install libxapian-1.3-5. Then it worked.

cavsfan@cavsfan-le-beast:~$ sudo dpkg -P libxapian-1.3-4 1.3.3-0ubuntu2
(Reading database ... 250782 files and directories currently installed.)
Removing libxapian-1.3-4 (1.3.3-0ubuntu2) ...
Purging configuration files for libxapian-1.3-4 (1.3.3-0ubuntu2) ...
dpkg: warning: ignoring request to remove 1.3.3-0ubuntu2 which isn't installed
Processing triggers for libc-bin (2.21-0ubuntu5) ...
cavsfan@cavsfan-le-beast:~$ ud2
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt-get -f install' to correct these.
The following packages have unmet dependencies:
 python3-xapian1.3 : Depends: libxapian-1.3-5 but it is not installed
E: Unmet dependencies. Try using -f.
cavsfan@cavsfan-le-beast:~$ sudo apt-get install libxapian-1.3-5
Reading package lists... Done
Building dependency tree
Reading state information... Done
Suggested packages:
  xapian-tools
The following NEW packages will be installed:
  libxapian-1.3-5
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.