What is an African dress code?

Nelson Mandela, South Africa's first elected president showed off his "Madiba shirt". Which is  "Flowery and loose-fitting ..." This shirt gave him "...relaxed - and some would say less formal - appearance." In Kenya the speaker of the national assemply "...presides over a parliament with one of the most rigid dressing codes in Africa." In Kenya "A suit and tie is compulsory for male members of Parliament...and anything less would cause an MP to be thrown out of the house." Despite being thrown out some of the Kenyan parliamentarians have tried to go against the dress code which they say is "...colonial and unAfrican." Some of them decided to actually go to the parliament with "...flowering Nigerian "agbada" robes - and of course getting thrown out for it." I understand why they want to look all professional while at the parliament but what I don't understand is why they can't wear what is an African outfit which fots their culture? It's not like it looks unprofessional. It makes them look like they are proud to be African and to represent for their home.