What is the correct way to spawn a model to Gazebo using a Python script?

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Hey can you please share the entire code of this file. I am kind of stuck in the same problem. It would be a great help !!

Thanks! didn't work without the open( ).read() ! Full code:

from gazebo_msgs.srv import SpawnModel
spawn_model_client = rospy.ServiceProxy('/gazebo/spawn_sdf_model', SpawnModel)
spawn_model_client(
    model_name='ground_plane',
    model_xml=open('/usr/share/gazebo-9/models/ground_plane/model.sdf', 'r').read(),
    robot_namespace='/foo',
    initial_pose=Pose(),
    reference_frame='world'
)

Slightly modified this answer to include imports to make this executable as is:

from gazebo_msgs.srv import SpawnModel
import rospy
from geometry_msgs.msg import Pose
spawn_model_client = rospy.ServiceProxy('/gazebo/spawn_sdf_model', SpawnModel)
spawn_model_client(
    model_name='ground_plane',
    model_xml=open('/usr/share/gazebo-9/models/ground_plane/model.sdf', 'r').read(),
    robot_namespace='/foo',
    initial_pose=Pose(),
    reference_frame='world'
)

Hello everyone the code everyone shared seems to work well, but I found a problem I couldn't solve. After launching the model with the codes above, I searched for the model's odometry and geometry by typing rostopic list but I couldn't find anything and whenever I manually press on the model in the gazebo simulation, the program crashes. Has anyone solved this problem?

A node should be added to work properly.

Another modification:

from gazebo_msgs.srv import SpawnModel
import rospy
from geometry_msgs.msg import Pose
rospy.init_node('insert_object',log_level=rospy.INFO)
spawn_model_client = rospy.ServiceProxy('/gazebo/spawn_sdf_model', SpawnModel)
spawn_model_client(
model_name='ground_plane',
    model_xml=open('/usr/share/gazebo-9/models/ground_plane/model.sdf', 'r').read(),
    robot_namespace='/foo',
    initial_pose=Pose(),
    reference_frame='world'
)