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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 area(p):
 """Area of a polygone :param p: list of the points taken in any orientation, p[0] can differ from p[-1] :returns: area :complexity: linear """

    A = 0
    for i in range(len(p)):
        A += p[i - 1][0] * p[i][1] - p[i][0] * p[i - 1][1]
    return A / 2.