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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 UpdateNumberOfEventSources( self, number_of_consumed_sources, number_of_produced_sources):
 """Updates the number of event sources. Args: number_of_consumed_sources (int):
 total number of event sources consumed by the process. number_of_produced_sources (int):
 total number of event sources produced by the process. Returns: bool: True if either number of event sources has increased. Raises: ValueError: if the consumed or produced number of event sources is smaller than the value of the previous update. """

    consumed_sources_delta = 0
    if number_of_consumed_sources is not None:
      if number_of_consumed_sources < self.number_of_consumed_sources:
        raise ValueError(
            'Number of consumed sources smaller than previous update.')

      consumed_sources_delta = (
          number_of_consumed_sources - self.number_of_consumed_sources)

      self.number_of_consumed_sources = number_of_consumed_sources
      self.number_of_consumed_sources_delta = consumed_sources_delta

    produced_sources_delta = 0
    if number_of_produced_sources is not None:
      if number_of_produced_sources < self.number_of_produced_sources:
        raise ValueError(
            'Number of produced sources smaller than previous update.')

      produced_sources_delta = (
          number_of_produced_sources - self.number_of_produced_sources)

      self.number_of_produced_sources = number_of_produced_sources
      self.number_of_produced_sources_delta = produced_sources_delta

    return consumed_sources_delta > 0 or produced_sources_delta > 0