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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 read(self, n):
 """Read data from file segs. Args: n: max bytes to read. Must be positive. Returns: some bytes. May be smaller than n bytes. "" when no more data is left. """

    if self._EOF:
      return ""

    while self._seg_index <= self._last_seg_index:
      result = self._read_from_seg(n)
      if result != "":
        return result
      else:
        self._next_seg()

    self._EOF = True
    return ""