def listarraytranspose(L):
    '''
    Tranposes the simple array presentation of a list of lists (of equal length).
    Argument:
        L = [row1, row2, ...., rowN]
        where the rowi are python lists of equal length.
    Returns:
        LT, a list of python lists such that LT[j][i] = L[i][j].
    '''
    return [[row[i] for row in L] for i in range(len(L[0]))]