Assign multiple values to variables with a function in a class

Question

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

• Peilonrayz: Thank you for the edit, this looks good. :)
• Halavus: I have to add, that I'm trying here to convert a bad written stand alone python script into a module for a webapp. I'm not sure if the whole process should be re-thinked. Maybe the use of a class is not the right one?

Answer 1

Use parens:

(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()

• Halavus: Those variables may be stored in a tupple?
• Peilonrayz: @Halavus self.get_row returns a tuple. 1, 2 is short hand for (1, 2).
• RootTwo: The target (the left hand side) of an assignment statement can be an iterable such as a list or tuple. Here, the commas make it a tuple, the parens just let it span multiple lines. You could use '[' and ']' instead.