How to update a ParameterScale?

[MaxGhenis]

I'd like to update a child allowance value. Child allowances are the 0th element in parameters.contrib.ubi_center.basic_income.amount_by_age. I get an error when trying to assign it. Here's the notebook.

from openfisca_us.api import *

def modify_parameters(parameters):
    parameters.contrib.ubi_center.basic_income.amount_by_age[0].update(
        period=periods.period("year:2020:1"),
        value=100
    )
    return parameters


class add_child_allowance(Reform):
    def apply(self):
        self.modify_parameters(modify_parameters)

mreformed = Microsimulation(add_child_allowance, year=2020)

AttributeError: 'ParameterScaleBracket' object has no attribute 'update'

I also tried this but it produced the same error:

    parameters.contrib.ubi_center.basic_income.amount_by_age.update(
        period=periods.period("year:2020:1"),
        value=[100, 0, 0]
    )

[nikhilwoodruff]

That cell works for me when modified to:

from openfisca_us.api import *
from openfisca_core import periods

def modify_parameters(parameters):
    parameters.contrib.ubi_center.basic_income.amount_by_age.brackets[0].amount.update(
        period=periods.period("year:2020:1"),
        value=100
    )
    return parameters


class add_child_allowance(Reform):
    def apply(self):
        self.modify_parameters(modify_parameters)

mreformed = Microsimulation(add_child_allowance, year=2020)

So, I think we need to use the brackets child before [0], and also import periods from openfisca_core.