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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 alt_blend_value(data, i, j, k):
 """Computes the average value of the three vertices of a triangle in the simplex triangulation, where two of the vertices are on the upper horizontal."""


    keys = alt_triangle_coordinates(i, j, k)
    return blend_value(data, i, j, k, keys=keys)