from sympy import Symbol, Eq
from sympy.solvers.solveset import solveset, nonlinsolve, linsolve
from IPython.display import display

assets = Symbol("assets")
equity = Symbol("equity")
liabilities = Symbol("liabilities")
capital = Symbol("capital")
retained_earnings = Symbol("retained earnings")
net_income = Symbol("net income")
dividends = Symbol("dividends")
income = Symbol("income")
expenses = Symbol("expenses")
avg_sales_price = Symbol("avg sales price")
sales_count = Symbol("sales count")

Vars = [
    assets,
    equity,
    liabilities,
    capital,
    retained_earnings,
    net_income,
    dividends,
    income,
    expenses,
    avg_sales_price,
    sales_count
]

Formulas = [
    Eq(assets, equity+liabilities),
    Eq(equity, capital+retained_earnings),
    Eq(retained_earnings, net_income-dividends),
    Eq(net_income, income-expenses),
    Eq(income/avg_sales_price,sales_count),
    Eq(avg_sales_price,2),
    Eq(sales_count,5)
]

# Answer should be 10, but instead:

#display(solveset(Formulas,income))   # ValueError: ... not a valid SymPy expression
display(nonlinsolve(Formulas,income)) # {(expenses + netincome)}
display(linsolve(Formulas,income))    # ∅