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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 _landsat_get_mtl(sceneid):
 """ Get Landsat-8 MTL metadata. Attributes sceneid : str Landsat sceneid. For scenes after May 2017, sceneid have to be LANDSAT_PRODUCT_ID. Returns ------- out : dict returns a JSON like object with the metadata. """

    scene_params = _landsat_parse_scene_id(sceneid)
    meta_file = "http://landsat-pds.s3.amazonaws.com/{}_MTL.txt".format(
        scene_params["key"]
    )
    metadata = str(urlopen(meta_file).read().decode())
    return toa_utils._parse_mtl_txt(metadata)