'Unmount a file system.
:param mount_point: path on the file system that is mounted.
:type mount_point: ``str``'

def _unmount(self, mount_point):

    build_command = [self.module.get_bin_path('umount', True), mount_point]
    (rc, stdout, err) = self._run_command(build_command)
    if (rc != 0):
        self.failure(err=err, rc=rc, msg=('failed    to    unmount    [    %s    ]' % mount_point), command='    '.join(build_command))
