Assign multiple values to variables with a function in a class

I would like to use this feature

>>> def func():
>>>     return 1, 2
>>> x, y = func()

But I have a formatting problem, because I want to assign values in the __init__() of a Class.

import csv

class Filewriter:
    def __init__(self, jsonstring, filepath):
        self.katAsk, self.katBid, self.promAsk, self.promBid, self.montAsk, self.montBid, self.katProm, self.katMont, self.promKat, self.promMont, self.montKat, self.montProm, self.ticker = self.get_row()

        self.jsonstring = jsonstring
        self.filepath = filepath

    def jsonparse(self, ticker, label):
        try:
            output = self.jsonstring[ticker][label]
        except (KeyError, ValueError) as e:
            output = None
        return output

    def test(self, teststring, ticker, cx):
        return self.jsonparse(ticker, cx+"."+teststring)

    def get_row(self, ticker):

        checkdic = {"ticker": ticker}
        # Check if asks/bids exist
        checkdic["cx"] = "CI1"
        try:
            katAsk = float(self.test("ask", **checkdic))
        except (TypeError, ValueError) as e:
            katAsk = -1

        try:
            katBid = float(self.test("bid", **checkdic))
        except (TypeError, ValueError) as e:
            katBid = -1

        checkdic["cx"]="IC1"
        try:
            promAsk = float(self.test("ask", **checkdic))
        except (TypeError, ValueError) as e:
        promAsk = -1
        try:
            promBid = float(self.test("bid", **checkdic))
        except (TypeError, ValueError) as e:
            promBid = -1

        checkdic["cx"]="NC1"
        try:
            montAsk = float(self.test("ask", **checkdic))
        except (TypeError, ValueError) as e:
            montAsk = -1
        try:
            montBid = float(self.test("bid", **checkdic))
        except (TypeError, ValueError) as e:
            montBid = -1

        # bidDest - askSource = sales
        # Determine sales
        # Kat -> Prom
        if(promBid > 0 and katAsk > 0):
            katProm = promBid - katAsk
        else:
            katProm = -1

        # Kat -> Mont
        if(montBid > 0 and katAsk > 0):
            katMont = montBid - katAsk
        else:
            katMont = -1

        # Prom -> Kat
        if(katBid > 0 and promAsk > 0):
            promKat = katBid - promAsk
        else:
            promKat = -1

        # Prom -> Mont
        if(montBid > 0 and promAsk > 0):
            promMont = montBid - promAsk
        else:
            promMont = -1

        # Mont -> Kat
        if(katBid > 0 and montAsk > 0):
            montKat = katBid - montAsk
        else:
            montKat = -1

        # Mont -> Prom
        if(promBid > 0 and montAsk > 0):
            montProm = promBid - montAsk
        else:
            montProm = -1

        return katAsk, katBid, promAsk, promBid, montAsk, montBid, katProm, katMont, promKat, promMont, montKat, montProm, ticker

    def tablewriter(self):
        with open(self.filepath, mode='w', newline='') as ag:
            agWriter = csv.writer(ag, delimiter=',',
                                  quotechar='"',
                                  quoting=csv.QUOTE_MINIMAL)

            agWriter.writerow([self.ticker,
                               self.katAsk,
                               self.katBid,
                               self.promAsk,
                               self.promBid,
                               self.montAsk,
                               self.montBid,
                               "",
                               self.katProm,
                               self.katMont,
                               self.promKat,
                               self.promMont,
                               self.montKat,
                               self.montProm,
                               "",
                               ])

Is it possible to format this statement on more than one line ?

edit: edited with real code

edit2: noticed a missing "self." before test() calls