rosdep install turtlesim does not work

[IdaChenCCL]

When input rosdep install turtlesim, the error message below shows up. It seems that the std_srvs should be defined. Where can I find this?

ERROR: the following packages/stacks could not have their rosdep keys resolved
to system dependencies:
turtlesim: No definition of [std_srvs] for OS [windows]

I tried the command below. The error message is stills there.
rosdep install --from-paths src --ignore-src --rosdistro=${ROS_DISTRO} -y --os=windows:xenial