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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 StartTiming(self, profile_name):
 """Starts timing CPU time. Args: profile_name (str):
 name of the profile to sample. """

    if profile_name not in self._profile_measurements:
      self._profile_measurements[profile_name] = CPUTimeMeasurement()

    self._profile_measurements[profile_name].SampleStart()