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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 find_bucket(self, bucketing_id, parent_id, traffic_allocations):
 """ Determine entity based on bucket value and traffic allocations. Args: bucketing_id: ID to be used for bucketing the user. parent_id: ID representing group or experiment. traffic_allocations: Traffic allocations representing traffic allotted to experiments or variations. Returns: Entity ID which may represent experiment or variation. """


    bucketing_key = BUCKETING_ID_TEMPLATE.format(bucketing_id=bucketing_id, parent_id=parent_id)
    bucketing_number = self._generate_bucket_value(bucketing_key)
    self.config.logger.debug('Assigned bucket %s to user with bucketing ID "%s".' % (
      bucketing_number,
      bucketing_id
    ))

    for traffic_allocation in traffic_allocations:
      current_end_of_range = traffic_allocation.get('endOfRange')
      if bucketing_number < current_end_of_range:
        return traffic_allocation.get('entityId')

    return None