[Python] TypeError: unsupported operand type(s) for *: 'int' and 'Var'

below is my gurobipy code

from gurobipy import Model, GRB, quicksum
import math

# Parameters
n = 314
m = 2025

# Pre-compute possible binomial coefficients
bin_coeffs = {(m - k, n): math.comb(m - k, n)
for k in range(m + 1) if m - k >= n}

# Create model
model = Model("binomial_minimization")

# Add variables
x = model.addVars(n, vtype=GRB.INTEGER, lb=1, ub=m, name="x")

# Add constraint
model.addConstr(quicksum(x for i in range(n)) == m, "sum_constraint")

# Create binary variables for each possible value of (m-x_k)
y = model.addVars(n, m + 1, vtype=GRB.BINARY, name="y")

# Link x and y variables
for i in range(n):
model.addConstr(x == quicksum(k * y[i,k] for k in range(m + 1)))
model.addConstr(quicksum(y[i,k] for k in range(m + 1)) == 1)

# Set objective
obj = quicksum(bin_coeffs.get((m - k, n), 0) * y[i,k]
for i in range(n) for k in range(m + 1))
model.setObjective(obj, GRB.MINIMIZE)

# Optimize
model.optimize()

# Print results
if model.status == GRB.OPTIMAL:
print("\nOptimal solution found:")
for i in range(n):
print(f"x[{i}] = {x.X}")
print(f"Objective value = {model.ObjVal}")


There is an error TypeError: unsupported operand type(s) for *: 'int' and 'Var'

for 'obj = quicksum(bin_coeffs.get((m - k, n), 0) * y[i,k] for i in range(n) for k in range(m + 1))'

How to fix it? The code works correctly for n=30, m=2025

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