Here's a basic calculator code in Python which can perform addition, subtraction, multiplication, and division:

```
# Function to add two numbers
def add(x, y):
    return x + y

# Function to subtract two numbers
def subtract(x, y):
    return x - y

# Function to multiply two numbers
def multiply(x, y):
    return x * y

# Function to divide two numbers
def divide(x, y):
    return x / y

print("Select operation.")
print("1.Add")
print("2.Subtract")
print("3.Multiply")
print("4.Divide")

# Take input from the user
choice = input("Enter choice (1/2/3/4): ")

num1 = int(input("Enter first number: "))
num2 = int(input("Enter second number: "))

if choice == '1':
    print(num1, "+", num2, "=", add(num1,num2))

elif choice == '2':
    print(num1, "-", num2, "=", subtract(num1,num2))

elif choice == '3':
    print(num1, "*", num2, "=", multiply(num1,num2))

elif choice == '4':
    print(num1, "/", num2, "=", divide(num1,num2))
else:
    print("Invalid input")
```
Scrivi poche righe di codice per creare una calcolatrice di base in Python.