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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 permission_request_approve_link(context, perm):
 """ Renders a html link to the approve view of the given permission request. Returns no content if the request-user has no permission to delete foreign permissions. """

    user = context['request'].user
    if user.is_authenticated():
        if user.has_perm('authority.approve_permission_requests'):
            return base_link(context, perm, 'authority-approve-permission-request')
    return {'url': None}