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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 from_list(cls, l):
 """Return a Point instance from a given list"""

        if len(l) == 3:
                x, y, z = map(float, l)
                return cls(x, y, z)
        elif len(l) == 2:
            x, y = map(float, l)
            return cls(x, y)
        else:
            raise AttributeError