>>> analyse_frequence_alphabet('gafesxgdtxqhzgxmadjcfghzeshqrfadjcfgxmyf...')
[['a', 0.064], ['b', 0.014], ['c', 0.04], ['d', 0.085], ['e', 0.017], ['f', 0.114], ['g', 0.093], 
['h', 0.072], ['i', 0.002], ['j', 0.027], ['k', 0.01], ['l', 0.001], ['m', 0.023], ['n', 0.024], 
 ['o', 0.001], ['p', 0.011], ['q', 0.078], ['r', 0.025], ['s', 0.073], ['t', 0.028], ['u', 0.009], 
 ['v', 0.009], ['w', 0.0], ['x', 0.072], ['y', 0.036], ['z', 0.075]]