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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def RenameGroup(r, group, new_name):
 """ Changes the name of a node group. @type group: string @param group: Node group name @type new_name: string @param new_name: New node group name @rtype: int @return: job id """


    body = {
        "new_name": new_name,
    }

    return r.request("put", "/2/groups/%s/rename" % group, content=body)