>>> analyse_frequence_alphabet("slylsfnxakxhtxyqjxssxbtlylsfnxuxakxhtxyrxnxnq...")
[['a', 0.023], ['b', 0.04], ['c', 0.008], ['d', 0.009], ['e', 0.032], ['f', 0.012], ['g', 0.012], 
['h', 0.017], ['i', 0.0], ['j', 0.064], ['k', 0.062], ['l', 0.069], ['m', 0.0], ['n', 0.082], 
['o', 0.008], ['p', 0.001], ['q', 0.081], ['r', 0.035], ['s', 0.065], ['t', 0.053], ['u', 0.033], 
['v', 0.024], ['w', 0.006], ['x', 0.202], ['y', 0.063], ['z', 0.001]]