turtlemimic.launch error

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Hello,

I used the command as given in the tutorials: roslaunch beginner_tutorials turtlemimic.launch.

On running it, I am receiving the following error:

Traceback (most recent call last):
  File "/opt/ros/jade/lib/python2.7/dist-packages/roslaunch/__init__.py", line 225, in main
    args = rlutil.resolve_launch_arguments(args)
  File "/opt/ros/jade/lib/python2.7/dist-packages/roslaunch/rlutil.py", line 92, in resolve_launch_arguments
    resolved = roslib.packages.find_resource(args[0], args[1])
  File "/opt/ros/jade/lib/python2.7/dist-packages/roslib/packages.py", line 504, in find_resource
    source_path_to_packages=source_path_to_packages)
  File "/opt/ros/jade/lib/python2.7/dist-packages/catkin/find_in_workspaces.py", line 142, in find_in_workspaces
    source_path_to_packages[source_path] = find_packages(source_path)
  File "/usr/lib/python2.7/dist-packages/catkin_pkg/packages.py", line 83, in find_packages
    packages = find_packages_allowing_duplicates(basepath, exclude_paths=exclude_paths, exclude_subspaces=exclude_subspaces, warnings=warnings)
  File "/usr/lib/python2.7/dist-packages/catkin_pkg/packages.py", line 110, in find_packages_allowing_duplicates
    packages[path] = parse_package(os.path.join(basepath, path), warnings=warnings)
  File "/usr/lib/python2.7/dist-packages/catkin_pkg/package.py", line 370, in parse_package
    return parse_package_string(f.read(), filename, warnings=warnings)
  File "/usr/lib/python2.7/dist-packages/catkin_pkg/package.py", line 413, in parse_package_string
    pkg.description = _get_node_value(_get_node(root, 'description'), allow_xml=True, apply_str=False)
  File "/usr/lib/python2.7/dist-packages/catkin_pkg/package.py", line 555, in _get_node
    raise InvalidPackage('The manifest must contain exactly one "%s" tags' % tagname)
InvalidPackage: Invalid package manifest "/home/shobhit/catkin_ws/src/beginner_tutorials/package.xml": The manifest must contain exactly one "description" tags

I have also run the source package. Please help!