Blank world when running ROS diff drive demo world on Eloquent

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When running the following, a Gazebo window appears but its blank with no sample model

samyak@samyak-VirtualBox:~/ws$ gazebo --verbose /opt/ros/eloquent/share/gazebo_plugins/worlds/gazebo_ros_diff_drive_demo.world
Gazebo multi-robot simulator, version 9.14.0
Copyright (C) 2012 Open Source Robotics Foundation.
Released under the Apache 2 License.
http://gazebosim.org

[Msg] Waiting for master.
Gazebo multi-robot simulator, version 9.14.0
Copyright (C) 2012 Open Source Robotics Foundation.
Released under the Apache 2 License.
http://gazebosim.org

[Msg] Waiting for master.
[Msg] Connected to gazebo master @ http://127.0.0.1:11345
[Msg] Publicized address: 10.0.2.15
[ INFO] [1599015953.295866899]: DiffDrive missing <robotNamespace>, defaults is vehicle
[FATAL] [1599015953.295989695]: You must call ros::init() before creating the first NodeHandle
[ERROR] [1599015953.299702408]: [registerPublisher] Failed to contact master at [:0].  Retrying...
[Msg] Connected to gazebo master @ http://127.0.0.1:11345
[Msg] Publicized address: 10.0.2.15