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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 LengthMeters(self):
 """Return length of this polyline in meters."""

    assert(len(self._points) > 0)
    length = 0
    for i in range(0, len(self._points) - 1):
      length += self._points[i].GetDistanceMeters(self._points[i+1])
    return length