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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 _decode_geom(ewkb):
 """Decode encoded wkb into a shapely geometry """

    # it's already a shapely object
    if hasattr(ewkb, 'geom_type'):
        return ewkb

    from shapely import wkb
    from shapely import wkt
    if ewkb:
        try:
            return wkb.loads(ba.unhexlify(ewkb))
        except Exception:
            try:
                return wkb.loads(ba.unhexlify(ewkb), hex=True)
            except Exception:
                try:
                    return wkb.loads(ewkb, hex=True)
                except Exception:
                    try:
                        return wkb.loads(ewkb)
                    except Exception:
                        try:
                            return wkt.loads(ewkb)
                        except Exception:
                            pass
    return None