python3 dump_instance.py 
s1
['/usr/bin/mydumper', '--compress', '--events', '--triggers', '--routines', "--logfile='/srv/backups/dump.s1.log'", "--outputdir='/srv/backups/s1.2018-02-27_13:34:12'", '--threads=16', '--host=dbstore2002.codfw.wmnet', '--port=3311', "--regex='^(.*wik.*|centralauth)\\.*$'"]
b'' b"\n** (mydumper:11540): CRITICAL **: Could not open log file ''/srv/backups/dump.s1.log'' for writing: 2\n"
s2
['/usr/bin/mydumper', '--compress', '--events', '--triggers', '--routines', "--logfile='/srv/backups/dump.s2.log'", "--outputdir='/srv/backups/s2.2018-02-27_13:34:13'", '--threads=16', '--host=db2044.codfw.wmnet', '--port=3306', "--regex='^((?!otrs\\.article_(plain|attachment)).)*$'"]
b'' b"\n** (mydumper:11541): CRITICAL **: Could not open log file ''/srv/backups/dump.s2.log'' for writing: 2\n"

jynus@merida:~/puppet/modules/profile/files/mariadb$ sudo mysql test
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 622
Server version: 10.1.26-MariaDB-0+deb9u1 Debian 9.1

Copyright (c) 2000, 2017, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [test]> SHOW TABLES;
+----------------+
| Tables_in_test |
+----------------+
| test           |
+----------------+
1 row in set (0.00 sec)

MariaDB [test]> SELECT * FROM test;
Empty set (0.00 sec)

MariaDB [test]> insert into test values (1), (2), (3);
Query OK, 3 rows affected (0.00 sec)
Records: 3  Duplicates: 0  Warnings: 0

MariaDB [test]> SELECT * FROM test;                   
+------+
| i    |
+------+
|    1 |
|    2 |
|    3 |
+------+
3 rows in set (0.00 sec)

MariaDB [test]> Bye
jynus@merida:~/puppet/modules/profile/files/mariadb$ cat /etc/mysql/backups.cnf 
user: 'dump'
password: 'dump'
sections:
  localhost:
    host: '127.0.0.1'
    socket: '/run/mysqld/mysqld.sock'
    archive: True

jynus@merida:~/puppet/modules/profile/files/mariadb$ python3 dump_sections.py            

jynus@merida:~/puppet/modules/profile/files/mariadb$ ls -lha /srv/backups/latest/
total 12K
drwxr-xr-x 3 jynus jynus 4.0K Mar  4 15:53 .
drwxr-xr-x 5 jynus jynus 4.0K Mar  4 12:17 ..
drwx------ 2 jynus jynus 4.0K Mar  4 15:53 dump.localhost.2018-03-04--15-52-56

jynus@merida:~/puppet/modules/profile/files/mariadb$ ls -lha /srv/backups/latest/dump.localhost.2018-03-04--15-52-56/
total 35M
drwx------ 2 jynus jynus 4.0K Mar  4 15:53 .
drwxr-xr-x 3 jynus jynus 4.0K Mar  4 15:53 ..
-rw-r--r-- 1 jynus jynus  35M Mar  4 15:53 employees.gz.tar
-rw-r--r-- 1 jynus jynus   75 Mar  4 15:53 metadata
-rw-r--r-- 1 jynus jynus 170K Mar  4 15:53 mysql.gz.tar
-rw-r--r-- 1 jynus jynus  10K Mar  4 15:53 test.gz.tar

jynus@merida:~/puppet/modules/profile/files/mariadb$ sudo mysql test
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 674
Server version: 10.1.26-MariaDB-0+deb9u1 Debian 9.1

Copyright (c) 2000, 2017, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [test]> DROP table test; # OPS
Query OK, 0 rows affected (0.02 sec)

MariaDB [test]> SELECT * FROM test;                   
ERROR 1146 (42S02): Table 'test.test' doesn't exist

jynus@merida:~/puppet/modules/profile/files/mariadb$ python3 recover_section.py localhost --host=127.0.0.1 --user=dump --password=dump --database=test
Attempting to recover "dump.localhost.2018-03-04--15-52-56" ...
Running myloader...

jynus@merida:~/puppet/modules/profile/files/mariadb$ sudo mysql test                  
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 692
Server version: 10.1.26-MariaDB-0+deb9u1 Debian 9.1

Copyright (c) 2000, 2017, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [test]> SELECT * FROM test;
+------+
| i    |
+------+
|    1 |
|    2 |
|    3 |
+------+
3 rows in set (0.00 sec)