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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 remove_group_role(request, role, group, domain=None, project=None):
 """Removes a given single role for a group from a domain or project."""

    manager = keystoneclient(request, admin=True).roles
    return manager.revoke(role=role, group=group, project=project,
                          domain=domain)