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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 sasdata(self, table: str, libref: str = '', results: str = '', dsopts: dict = None) -> 'SASdata': """ Method to define an existing SAS dataset so that it can be accessed via SASPy :param table: the name of the SAS Data Set :param libref: the libref for the Data Set, defaults to WORK, or USER if assigned :param results: format of results, SASsession.results is default, Pandas, HTML and TEXT are the valid options :param dsopts: a dictionary containing any of the following SAS data set options(where, drop, keep, obs, firstobs):
 - where is a string - keep are strings or list of strings. - drop are strings or list of strings. - obs is a numbers - either string or int - first obs is a numbers - either string or int - format is a string or dictionary { var: format } .. code-block:: python {'where' : 'msrp < 20000 and make = "Ford"' 'keep' : 'msrp enginesize Cylinders Horsepower Weight' 'drop' : ['msrp', 'enginesize', 'Cylinders', 'Horsepower', 'Weight'] 'obs' : 10 'firstobs' : '12' 'format' : {'money': 'dollar10', 'time': 'tod5.'} } :return: SASdata object """

        dsopts = dsopts if dsopts is not None else {}

        if results == '':
            results = self.results
        sd = SASdata(self, libref, table, results, dsopts)
        if not self.exist(sd.table, sd.libref):
            if not self.batch:
                print(
                    "Table " + sd.libref + '.' + sd.table + " does not exist. This SASdata object will not be useful until the data set is created.")
        return sd