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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def percentile(sorted_list, percent, key=lambda x: x):
 """Find the percentile of a sorted list of values. Arguments --------- sorted_list : list A sorted (ascending) list of values. percent : float A float value from 0.0 to 1.0. key : function, optional An optional function to compute a value from each element of N. Returns ------- float The desired percentile of the value list. Examples -------- 7.0 8.0 8.5 11.0 11.0 4.0 """

    if not sorted_list:
        return None
    if percent == 1:
        return float(sorted_list[-1])
    if percent == 0:
        return float(sorted_list[0])
    n = len(sorted_list)
    i = percent * n
    if ceil(i) == i:
        i = int(i)
        return (sorted_list[i-1] + sorted_list[i]) / 2
    return float(sorted_list[ceil(i)-1])