python - encode / décode la longueur de la course

　　Encodage / décodage:

def rle (s): 
    c = '' 
    p = '' 
    x = 1 
    pour _ in s: 
        si _ == p: 
            x + = 1 
        sinon: 
            c + = str (x) 
            c + = p 
            x = 1 
        p = _ 
    c + = str (x) 
    c + = p 
    return c [1:] 


def rld (s): 
    r = '' 
    n = 0 
    for _ in s: 
        if _.isdigit (): 
            n = int (_) 
        elif n> 0: 
            r + = _ * n 
    retour r 


s = 'aaaaaaassssssssgggrrrttaawefw' 
e = rle (s) 
print (e)

　　Sortie:

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