>>> from datetime import datetime
>>> from vehicles import Flota
>>> from autonoms import Autonom

--ini-enunciat
>>> m = Flota('Eltour')
>>> m.afeg_vehicle(Autonom('B05', 9.5))
>>> m.afeg_vehicle(Autonom('T73', 18.1))
>>> len(m)
2
>>> m[0].id, m[0].vel
('B05', 9.5)
>>> m.afeg_vehicle(Autonom('T56', 9.2))
>>> len(m)
3
>>> m[2].id, m[2].vel
('T56', 9.2)
>>> m.afeg_vehicle(Autonom('T56', 67.9))
>>> m[2].id, m[2].vel
('T56', 67.9)
>>> len(m)
3

--fi-enunciat
>>> m.afeg_vehicle(Autonom('XX34', 1.9))
>>> len(m)
4
>>> m[3].vel
1.9
>>> m.afeg_vehicle(Autonom('YY67', 0))
>>> len(m)
5
>>> m.afeg_vehicle(Autonom('YY67', 10))
>>> len(m)
5
>>> m[4].vel
10