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Start your free trial###### Marko Miokovic

5,132 Points# I can't figure it out what is wrong here. I am getting the error "Can't get the length of the 'Hand' ". Any suggestions?

Any suggestions?

```
import random
class Die:
def __init__(self, sides=2, value = 0):
if sides < 2:
raise ValueError("Can't have fewer than two sides")
self.sides = sides
self.value = value or random.randint(1, sides)
def __int__(self):
return self.value
def __add__(self, other):
return int(self) + other
def __radd__(self, other):
return self + other
def __repr__(self):
return str(self.value)
def __len__(self):
return len(self)
class D20(Die):
def __init__(self, sides = 2):
super().__init__(sides = 20)
```

```
from dice import D20
class Hand(list):
def __init__(self, size = 2, die_class = D20, *args, **kwargs):
self.die_class = die_class
self.size = size
super().__init__()
@property
def total(self):
return sum(self)
def roll(self, input):
if not isinstance(input, int):
raise ValueError("Input must be a whole number")
for _ in range(input):
self.append(self.die_class())
return self
```

## 1 Answer

###### Steven Parker

225,664 PointsYou're pretty close, but the instructions say the challenge will be calling *Hand.roll()*, which would suggest it should be a *class method*. They also say that it expects *"to get back an instance of Hand..."*, which implies that the

*roll*method will need to create a new instance and return it.

## Marko Miokovic

5,132 Points## Marko Miokovic

5,132 PointsThanks for the directions, it was helpfull :)