Understanding the Error
Receiving a ValueError: too many values to unpack (expected 2) typically indicates that you’re trying to unpack an iterable (like a list or tuple) into two variables, but the iterable contains more than two items. Python expects exactly two items to unpack, but if it encounters more, it raises this error.
Possible Solutions
Ensure Two-Item Iterables
Check your iterable source and ensure you’re providing an iterable with exactly two items. This can mean either adjusting the iterable itself or changing which parts of it you’re unpacking.
Example:
pair = (1, 2)
a, b = pair
print(a, b) # Prints: 1 2
Ignoring Excess Values
If your iterable contains more than two items, and you are only interested in the first two, you can use underscore (_) as a placeholder for the remaining items. This tells Python to ignore additional values.
Example:
data = (1, 2, 3, 4)
a, b, *_ = data
print(a, b) # Prints: 1 2
Extended Unpacking
In case you need the first two values and also want to preserve the rest, Python allows for extended unpacking using a star expression (*). Assign the first two values to individual variables and the rest to a list.
Example:
data = (1, 2, 3, 4)
a, b, *rest = data
print(a, b) # Prints: 1 2
print(rest) # Prints: [3, 4]
That’s it. Happy coding!
