class ControllerDayWise(ReportBuilder):
    #..........
class ControllerBulkReport(ReportBuilder):
    #..........
class ControllerBreakdownByAge(ReportBuilder):
    #..........

class ExampleController:
    def __init__(self, report_builder_factory):
        # report builder factory could be either a function or an instance of a class
        self.report_builder_factory = report_builder_factory

    def get_daterange_report(self, start, end):
        report = self.report_builder_factory().set_date_range(start, end).execute()
        return report # Wrap this in whatever your framework provides for successful responses