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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_convex_hull(self):
 """ Get a convex polygon object that contains projections of all the points of the mesh. :returns: Instance of :class:`openquake.hazardlib.geo.polygon.Polygon` that is a convex hull around all the points in this mesh. If the original mesh had only one point, the resulting polygon has a square shape with a side length of 10 meters. If there were only two points, resulting polygon is a stripe 10 meters wide. """

        proj, polygon2d = self._get_proj_convex_hull()
        # if mesh had only one point, the convex hull is a point. if there
        # were two, it is a line string. we need to return a convex polygon
        # object, so extend that area-less geometries by some arbitrarily
        # small distance.
        if isinstance(polygon2d, (shapely.geometry.LineString,
                                  shapely.geometry.Point)):
            polygon2d = polygon2d.buffer(self.DIST_TOLERANCE, 1)

        # avoid circular imports
        from openquake.hazardlib.geo.polygon import Polygon
        return Polygon._from_2d(polygon2d, proj)