Wsrtjtyk

I am programming a version of the public goods game but using roles. Because of that, i cant obtain the sum of the total contributions of the players who are from a determined role. I tried with the following code:

self.total_contribution1 = sum(
[p.contribution for p in self.get_players() if p.role== 'A'])

But it didn't worked and i only obtained an error of Invalid Operation

If i dont write the "if part" of that code, it runs, but the values of the attributes like that one become 0

from otree.api import (

models, widgets, BaseConstants, BaseSubsession, BaseGroup, BasePlayer,

Currency as c, currency_range

)

import random

import floppyforms as forms

import config_leex_1



author = 'Your name here'



doc = """

Simple public goods game

"""





class Constants(BaseConstants):

name_in_url = 'tiebout_incertidumbre'

players_per_group = 4

num_rounds = config_leex_1.PEMG_number_rounds #10

instructions_template = 'beec_mg/Instructions.html'

multiplier1 = 1

multiplier2 = 2

multiplier3 = 3

i = 1

j = 1

k = 1



class Subsession(BaseSubsession):

def creating_session(self):



    for p in self.get_players():

        p.endowment = random.randint(1, 100)

        p.prob = random.randint(0,100)

        # Random creation of endowments for every round



class Group(BaseGroup):



    total_contribution1 = models.CurrencyField(initial=0)

    total_contribution2 = models.CurrencyField(initial=0)

    total_contribution3 = models.CurrencyField(initial=0)

    mean_contribution1 = models.CurrencyField(initial=0)

    mean_contribution2 = models.CurrencyField(initial=0)

    mean_contribution3 = models.CurrencyField(initial=0)

    totalp1 = models.IntegerField(initial=0)

    totalp2 = models.IntegerField(initial=0)

    totalp3 = models.IntegerField(initial=0)

    individual_share1 = models.CurrencyField(initial=0)

    individual_share2 = models.CurrencyField(initial=0)

    individual_share3 = models.CurrencyField(initial=0)



    def set_payoffs(self):

        # NOTA 1: LAS SUMAS CON FOR NO ESTÁN FUNCIONANDO, YA QUE DAN DE         

        VALOR 0

        # NOTA 2: Los sums con if botan un error de invalid operation

        # NOTA 3: Segun SO, se deberia incluir parentesis después de p.role

    # if p.role== 'A':

    # self.total_contribution1 = sum(

        # [p.contribution for p in self.get_players() if p.role() == 'A'])

        for p in self.get_players():

            if p.role() == 'A':

                self.total_contribution1=+ p.contribution



        for p in self.get_players():

            if p.role() == 'B':

                self.total_contribution2=+ p.contribution



        for p in self.get_players():

            if p.role() == 'C':

                self.total_contribution3=+ p.contribution



        # if p.role== 'B'

        # self.total_contribution2 = sum(

        # [p.contribution for p in self.get_players()])

        # if p.role== 'C'

        # self.total_contribution3 = sum(

        # [p.contribution for p in self.get_players()])



        # if p.role== 'A'

        # self.totalp1 = sum(

        # [p.counter for p in self.get_players() if p.role() == 'A'])

        for p in self.get_players():

            if p.role() == 'A':

                self.totalp1=+1



        for p in self.get_players():

            if p.role() == 'B':

                self.totalp2=+1



        for p in self.get_players():

            if p.role() == 'C':

                self.totalp3=+1



        # if p.role == 'B'

    # self.totalp2 = sum(

        # [p.counter for p in self.get_players() if p.role() == 'B'])

    # if p.role == 'C'

    # self.totalp3 = sum(

        # [p.counter for p in self.get_players() if p.role() == 'C'])



    self.individual_share1 = self.total_contribution1 *         

    Constants.multiplier1 / self.totalp1

    self.individual_share2 = self.total_contribution2 *                 

    Constants.multiplier2 / self.totalp2

    self.individual_share3 = self.total_contribution3 * 

    Constants.multiplier3 / self.totalp3



    self.mean_contribution1 = self.total_contribution1/self.totalp1

    self.mean_contribution2 = self.total_contribution2 /self.totalp2

    self.mean_contribution3 = self.total_contribution3 /self.totalp3





    for p in self.get_players():

        if p.role == "A":

            p.payoff = p.endowment - p.contribution + self.individual_share1

        elif p.role == "B":

            if p.prob <= 75:

                p.payoff = p.endowment - p.contribution + 

    self.individual_share2

            else:

                p.payoff = p.endowment - p.contribution

        else:

            if p.prob <= 50:

                p.payoff = p.endowment - p.contribution + 

    self.individual_share3

            else:

                p.payoff = p.endowment - p.contribution



class Player(BasePlayer):

    prob =models.IntegerField(min=0, max=100)

    endowment = models.CurrencyField(min=0, max=100, initial=0)

    contribution = models.CurrencyField(verbose_name='Deslice hasta 

    seleccionar la cantidad a enviar deseada',

                                    min=0,max=100,

                                    initial=0,widget=widgets.SliderInput())

    counter = models.IntegerField(initial=1)

    roller = models.IntegerField(verbose_name='Deslice hasta seleccionar el 

    número de la opción deseada',

                             min=1, max=3,

                             widget=widgets.SliderInput())

   # Se está usando un slider para esta opción pues permite evitar 

   confusiones en caso se use un grupo de botones

   # los cuales se podrían clickear en cualquier momento sin que el jugador 

   entienda si ya se registró o no su decisión



   def role(self):

      if self.roller == 1:

          return 'A'

      elif self.roller == 2:

          return 'B'

      else:

          return 'C'from otree.api import (

role is a method not a field.
so to make it work you need to use this:

self.total_contribution1 = sum( [p.contribution for p in self.get_players() if p.role() == 'A'])

Attention to the parentheses I added after role