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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 embedded_preview(src_path):
  ''' Returns path to temporary copy of embedded QuickLook preview, if it exists '''
  try:
    assert(exists(src_path) and isdir(src_path))

    preview_list = glob(join(src_path, '[Q|q]uicklook', '[P|p]review.*'))
    assert(preview_list)  # Assert there's at least one preview file
    preview_path = preview_list[0]  # Simplistically, assume there's only one

    with NamedTemporaryFile(prefix='pyglass', suffix=extension(preview_path), delete=False) as tempfileobj:
      dest_path = tempfileobj.name
      shutil.copy(preview_path, dest_path)

    assert(exists(dest_path))
    return dest_path
  except:
    return None