diff -Nru metaphlan2-2.7.5/debian/changelog metaphlan2-2.7.5/debian/changelog
--- metaphlan2-2.7.5/debian/changelog	2018-02-16 11:12:16.000000000 +0100
+++ metaphlan2-2.7.5/debian/changelog	2019-04-24 21:17:24.000000000 +0200
@@ -1,3 +1,9 @@
+metaphlan2 (2.7.5-1ubuntu1) bionic; urgency=medium
+
+  * Backport a debian patch to fix installation error. (LP: #1777165)
+
+ -- Dylan Aïssi <daissi@debian.org>  Wed, 24 Apr 2019 21:17:24 +0200
+
 metaphlan2 (2.7.5-1) unstable; urgency=medium
 
   * New upstream version (no data shiped with this archive any more)
diff -Nru metaphlan2-2.7.5/debian/patches/_metaphlan2.py.patch metaphlan2-2.7.5/debian/patches/_metaphlan2.py.patch
--- metaphlan2-2.7.5/debian/patches/_metaphlan2.py.patch	1970-01-01 01:00:00.000000000 +0100
+++ metaphlan2-2.7.5/debian/patches/_metaphlan2.py.patch	2019-04-24 21:17:24.000000000 +0200
@@ -0,0 +1,43 @@
+Author: Tony Travis <tony.travis@minke-informatics.co.uk>
+Last-Update: Mon, 28 May 2018 01:36:48 +0100
+Origin: https://lists.debian.org/debian-med/2018/05/msg00071.html
+Description: Compile with Python2 despite _metaphlan2.py is using Python3 syntax
+ The "_metaphlan2.py" file contains Python 3 source but the "postinst"
+ script runs "pycompile" on the Python source files. However, "pycompile"
+ only supports Python version 2. The print() function in "_metaphlan2.py"
+ can be imported from the "__future__" library, but Python 2 does not
+ support function annotations: These are optional in Python 3, and are
+ removed from the function definitions in "_metaphlan2.py" by the patch.
+Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/metaphlan2/+bug/1777165
+
+--- a/_metaphlan2.py
++++ b/_metaphlan2.py
+@@ -3,7 +3,7 @@
+ # This module defines the functions which run MetaPhlAn2 on
+ # single and paired fastq data.
+ 
+-
++from __future__ import print_function
+ import subprocess as sb
+ from q2_types.per_sample_sequences import SingleLanePerSampleSingleEndFastqDirFmt
+ from q2_types.per_sample_sequences import SingleLanePerSamplePairedEndFastqDirFmt
+@@ -24,8 +24,7 @@ def metaphlan2_helper(raw_data, nproc, i
+     sb.run(cmd, check=True)
+ 
+ 
+-def profile_single_fastq(raw_data: SingleLanePerSampleSingleEndFastqDirFmt,
+-                         nproc: int=1) -> biom.Table:
++def profile_single_fastq(raw_data, nproc=1):
+     output_biom = None
+ 
+     with tempfile.TemporaryDirectory() as tmp_dir:
+@@ -36,8 +35,7 @@ def profile_single_fastq(raw_data: Singl
+     return output_biom
+ 
+ 
+-def profile_paired_fastq(raw_data: SingleLanePerSamplePairedEndFastqDirFmt,
+-                         nproc: int=1) -> biom.Table:
++def profile_paired_fastq(raw_data, nproc=1):
+     output_biom = None
+ 
+     with tempfile.TemporaryDirectory() as tmp_dir:
diff -Nru metaphlan2-2.7.5/debian/patches/series metaphlan2-2.7.5/debian/patches/series
--- metaphlan2-2.7.5/debian/patches/series	2018-02-16 11:12:16.000000000 +0100
+++ metaphlan2-2.7.5/debian/patches/series	2019-04-24 21:17:24.000000000 +0200
@@ -1,2 +1,3 @@
 mpa_dir-is-usr_share_metaphlan2.patch
 spelling.patch
+_metaphlan2.py.patch