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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 get_slot_position(self, container, type='a'):
 """Returns the slot where the analyses from the type and container passed in are located within the worksheet. :param container: the container in which the analyses are grouped :param type: type of the analysis :return: the slot position :rtype: int """

        if not container or type not in ALLOWED_ANALYSES_TYPES:
            return None
        uid = api.get_uid(container)
        layout = self.getLayout()

        for pos in layout:
            if pos['type'] != type or pos['container_uid'] != uid:
                continue
            return to_int(pos['position'])
        return None