def Fibb_Store(x, series=[1, 1]):
    """Optimized version for frequently used .
        it Generate Fibb List and Store it the fibb number range found in this 
        then it return or it extends list
    """
    z = len(series)
    if x < z:
        return series[x]
    else:
        for i in range(z, x):
            series.append(series[i - 2] + series[i - 1])
        return series[x - 1]
