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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 _dump_to_pages(dump):
 """Extract pages from an xml dump. Args: dump: a unicode string Returns: a list of unicode strings """

  pos = 0
  ret = []
  start_tag = u"<page>\n"
  end_tag = u"</page>\n"
  while True:
    start_pos = dump.find(start_tag, pos)
    if start_pos == -1:
      break
    start_pos += len(start_tag)
    end_pos = dump.find(end_tag, start_pos)
    if end_pos == -1:
      break
    ret.append(dump[start_pos:end_pos])
    pos = end_pos + len(end_tag)
  return ret