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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 to_timestamp(dt, timestamp):
 """Convert datetime to google.protobuf.Timestamp. Args: dt: a timezone naive datetime. timestamp: a google.protobuf.Timestamp to populate. Raises: TypeError: if a timezone aware datetime was provided. """

  if dt.tzinfo:
    # this is an "aware" datetime with an explicit timezone. Throw an error.
    raise TypeError('Cannot store a timezone aware datetime. '
                    'Convert to UTC and store the naive datetime.')
  timestamp.seconds = calendar.timegm(dt.timetuple())
  timestamp.nanos = dt.microsecond * _NANOS_PER_MICRO