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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 triangle_area(pt1, pt2, pt3):
 r"""Return the area of a triangle. Parameters pt1: (X,Y) ndarray Starting vertex of a triangle pt2: (X,Y) ndarray Second vertex of a triangle pt3: (X,Y) ndarray Ending vertex of a triangle Returns ------- area: float Area of the given triangle. """

    a = 0.0

    a += pt1[0] * pt2[1] - pt2[0] * pt1[1]
    a += pt2[0] * pt3[1] - pt3[0] * pt2[1]
    a += pt3[0] * pt1[1] - pt1[0] * pt3[1]

    return abs(a) / 2