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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 list_members(context, request):
 """Return the list of users in the group."""

    members = context.members()
    return {
        'users': [{
            'username': m.identifier,
            'userid': m.userid,
            'roles': context.get_member_roles(m.userid),
            'links': [rellink(m, request)]
        } for m in members]
    }