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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 _get_proj_convex_hull(self):
 """ Create a projection centered in the center of this mesh and define a convex polygon in that projection, enveloping all the points of the mesh. :returns: Tuple of two items: projection function and shapely 2d polygon. Note that the result geometry can be line or point depending on number of points in the mesh and their arrangement. """

        # create a projection centered in the center of points collection
        proj = geo_utils.OrthographicProjection(
            *geo_utils.get_spherical_bounding_box(self.lons, self.lats))

        # project all the points and create a shapely multipoint object.
        # need to copy an array because otherwise shapely misinterprets it
        coords = numpy.transpose(proj(self.lons.flat, self.lats.flat)).copy()
        multipoint = shapely.geometry.MultiPoint(coords)
        # create a 2d polygon from a convex hull around that multipoint
        return proj, multipoint.convex_hull