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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 find_previous(element, l):
 """ find previous element in a sorted list 0 1 1 2 """

    length = len(l)
    for index, current in enumerate(l):
        # current is the last element
        if length - 1 == index:
            return current

        # current is the first element
        if index == 0:
            if element < current:
                return None

        if current <= element < l[index+1]:
            return current