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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 _polygon_from_coords(coords, fix_geom=False, swap=True, dims=2):
 """ Return Shapely Polygon from coordinates. - coords: list of alterating latitude / longitude coordinates - fix_geom: automatically fix geometry """

    assert len(coords) % dims == 0
    number_of_points = len(coords)/dims
    coords_as_array = np.array(coords)
    reshaped = coords_as_array.reshape(number_of_points, dims)
    points = [
        (float(i[1]), float(i[0])) if swap else ((float(i[0]), float(i[1])))
        for i in reshaped.tolist()
        ]
    polygon = Polygon(points).buffer(0)
    try:
        assert polygon.is_valid
        return polygon
    except AssertionError:
        if fix_geom:
            return polygon.buffer(0)
        else:
            raise RuntimeError("Geometry is not valid.")