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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_proper_elastic_search_date_rounding_format(partial_date):
 """Returns the proper ES date math unit according to the "resolution" of the partial_date. Args: partial_date (PartialDate):
 The partial date for which the date math unit is. Returns: (str):
 The ES date math unit format. Notes: This is needed for supporting range queries on dates, i.e. rounding them up or down according to the ES range operator. For example, without this, a query like 'date > 2010-11', would return documents with date '2010-11-15', due to the date value of the query being interpreted by ES as '2010-11-01 01:00:00'. By using the suffixes for rounding up or down, the date value of the query is interpreted as '2010-11-30T23:59:59.999', thus not returning the document with date '2010-11-15', as the user would expect. See: https://www.elastic.co/guide/en/elasticsearch/reference/6.1/query-dsl-range-query.html#_date_math_and_rounding """

    es_date_math_unit = ES_DATE_MATH_ROUNDING_YEAR

    if partial_date.month:
        es_date_math_unit = ES_DATE_MATH_ROUNDING_MONTH
    if partial_date.day:
        es_date_math_unit = ES_DATE_MATH_ROUNDING_DAY

    return es_date_math_unit