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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 DeleteAttributes(self, subject, attributes, start=None, end=None, sync=True):
 """Remove some attributes from a subject."""

    _ = sync  # Unused
    if not attributes:
      return

    if isinstance(attributes, string_types):
      raise ValueError(
          "String passed to DeleteAttributes (non string iterable expected).")

    for attribute in attributes:
      timestamp = self._MakeTimestamp(start, end)
      attribute = utils.SmartUnicode(attribute)
      queries = self._BuildDelete(subject, attribute, timestamp)
      self._ExecuteQueries(queries)