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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_xyz(cls, x, y, z):
 """Creates GeoVector from Mercator slippy map values. """

        bb = xy_bounds(x, y, z)
        return cls.from_bounds(xmin=bb.left, ymin=bb.bottom,
                               xmax=bb.right, ymax=bb.top,
                               crs=WEB_MERCATOR_CRS)