Может ли Promise.all (). Finally () вернуть неразрешенные данные?

def matchingString(x,y):
    match=''
    for i in range(0,len(x)):
        for j in range(0,len(y)):
            k=1
            # now applying while condition untill we find a substring match and length of substring is less than length of x and y
            while (i+k <= len(x) and j+k <= len(y) and x[i:i+k]==y[j:j+k]):
                if len(match) <= len(x[i:i+k]):
                   match = x[i:i+k]
                k=k+1
    return match  

print matchingString('apple','ale') #le
print matchingString('apple pie available','apple pies') #apple pie