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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_classifications(subcategory_key):
 """Get hazard or exposure classifications. :param subcategory_key: The hazard or exposure key :type subcategory_key: str :returns: List of hazard or exposure classifications :rtype: list """

    classifications = definition(subcategory_key)['classifications']
    return sorted(classifications, key=lambda k: k['key'])