<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def DeleteGroup(r, group, dry_run=False):
 """ Deletes a node group. @type group: str @param group: the node group to delete @type dry_run: bool @param dry_run: whether to peform a dry run @rtype: int @return: job id """


    query = {
        "dry-run": dry_run,
    }

    return r.request("delete", "/2/groups/%s" % group, query=query)