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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_url_hashes(path):
 """Get hashes of urls in file."""

  urls = _read_text_file(path)
  def url_hash(u):
    h = hashlib.sha1()
    try:
      u = u.encode('utf-8')
    except UnicodeDecodeError:
      logging.error('Cannot hash url: %s', u)
    h.update(u)
    return h.hexdigest()
  return {url_hash(u): True for u in urls}