Error on installing devstack

Kindly help me successfully install devstack using the stack.sh script.

I get this error:

Enter a short description...2017-12-15 02:17:44.397 | Processing triggers for ufw (0.35-0ubuntu2) ...

2017-12-15 02:17:44.508 | WARN: Duplicate profile 'OpenSSH', using last found

2017-12-15 02:17:46.565 | +functions-common:apt_get:1118             result=0

2017-12-15 02:17:46.574 | +functions-common:apt_get:1121             time_stop apt-get

2017-12-15 02:17:46.582 | +functions-common:time_stop:2385           local name

2017-12-15 02:17:46.590 | +functions-common:time_stop:2386           local end_time

2017-12-15 02:17:46.599 | +functions-common:time_stop:2387           local elapsed_time

2017-12-15 02:17:46.607 | +functions-common:time_stop:2388           local total

2017-12-15 02:17:46.615 | +functions-common:time_stop:2389           local start_time

2017-12-15 02:17:46.623 | +functions-common:time_stop:2391           name=apt-get

2017-12-15 02:17:46.631 | +functions-common:time_stop:2392           start_time=1513304254

2017-12-15 02:17:46.639 | +functions-common:time_stop:2394           [[ -z 1513304254 ]]

2017-12-15 02:17:46.650 | ++functions-common:time_stop:2397           date +%s

2017-12-15 02:17:46.660 | +functions-common:time_stop:2397           end_time=1513304266

2017-12-15 02:17:46.668 | +functions-common:time_stop:2398           elapsed_time=12

2017-12-15 02:17:46.675 | +functions-common:time_stop:2399           total=34

2017-12-15 02:17:46.683 | +functions-common:time_stop:2401           _TIME_START[$name]=

2017-12-15 02:17:46.690 | +functions-common:time_stop:2402           _TIME_TOTAL[$name]=46

2017-12-15 02:17:46.698 | +functions-common:apt_get:1122             return 0

2017-12-15 02:17:46.705 | +lib/apache:install_apache_wsgi:78         enable_apache_mod wsgi

2017-12-15 02:17:46.713 | +lib/apache:enable_apache_mod:48           local mod=wsgi

2017-12-15 02:17:46.721 | +lib/apache:enable_apache_mod:50           is_ubuntu

2017-12-15 02:17:46.729 | +functions-common:is_ubuntu:466            [[ -z deb ]]

2017-12-15 02:17:46.737 | +functions-common:is_ubuntu:469            '[' deb = deb ']'

2017-12-15 02:17:46.745 | +lib/apache:enable_apache_mod:51           a2query -m wsgi

2017-12-15 02:17:46.794 | wsgi (enabled by maintainer script)

2017-12-15 02:17:46.803 | +lib/apache:install_apache_wsgi:83         sudo a2enmod version

2017-12-15 02:17:46.862 | ERROR: Module version does not exist!

2017-12-15 02:17:46.873 | +lib/apache:install_apache_wsgi:83         true

2017-12-15 02:17:46.880 | +lib/keystone:install_keystone:571         is_ssl_enabled_service key

2017-12-15 02:17:46.887 | +lib/tls:is_ssl_enabled_service:371        local services=key

2017-12-15 02:17:46.894 | +lib/tls:is_ssl_enabled_service:372        local service=

2017-12-15 02:17:46.901 | +lib/tls:is_ssl_enabled_service:373        '[' False == False ']'

2017-12-15 02:17:46.908 | +lib/tls:is_ssl_enabled_service:374        return 1

2017-12-15 02:17:46.915 | +lib/stack:stack_install_service:33        [[ False = True ]]

2017-12-15 02:17:46.923 | +./stack.sh:main:825                       configure_keystone

2017-12-15 02:17:46.932 | +lib/keystone:configure_keystone:200       sudo install -d -o ubuntu /et

c/keystone

2017-12-15 02:17:46.951 | +lib/keystone:configure_keystone:202       [[ /etc/keystone != \/\o\p\t\

/\s\t\a\c\k\/\k\e\y\s\t\o\n\e\/\e\t\c ]]

2017-12-15 02:17:46.960 | +lib/keystone:configure_keystone:203       install -m 600 /opt/stack/key

stone/etc/keystone.conf.sample /etc/keystone/keystone.conf

2017-12-15 02:17:46.970 | +lib/keystone:configure_keystone:204       cp -p /opt/stack/keystone/etc

/policy.json /etc/keystone

2017-12-15 02:17:46.973 | cp: cannot stat '/opt/stack/keystone/etc/policy.json': No such file or d

irectory

2017-12-15 02:17:46.983 | +lib/keystone:configure_keystone:1         exit_trap

2017-12-15 02:17:46.992 | +./stack.sh:exit_trap:494                  local r=1

2017-12-15 02:17:47.002 | ++./stack.sh:exit_trap:495                  jobs -p

2017-12-15 02:17:47.012 | +./stack.sh:exit_trap:495                  jobs=

2017-12-15 02:17:47.021 | +./stack.sh:exit_trap:498                  [[ -n '' ]]

2017-12-15 02:17:47.030 | +./stack.sh:exit_trap:504                  kill_spinner

2017-12-15 02:17:47.039 | +./stack.sh:kill_spinner:390               '[' '!' -z '' ']'

2017-12-15 02:17:47.047 | +./stack.sh:exit_trap:506                  [[ 1 -ne 0 ]]

2017-12-15 02:17:47.056 | +./stack.sh:exit_trap:507                  echo 'Error on exit'

2017-12-15 02:17:47.057 | Error on exit

2017-12-15 02:17:47.066 | +./stack.sh:exit_trap:508                  generate-subunit 1513304015 2

52 fail

2017-12-15 02:17:47.396 | +./stack.sh:exit_trap:509                  [[ -z /opt/stack/logs ]]

2017-12-15 02:17:47.407 | +./stack.sh:exit_trap:512                  /home/ubuntu/devstack/tools/w

orlddump.py -d /opt/stack/logs

2017-12-15 02:17:47.718 | +./stack.sh:exit_trap:518                  exit 1

ubuntu@devstack-cc:~/devstack$