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###### Steven Hender

5,830 Points# In Python I have a problems re-assigning '__imul__' I call 'NumString(3) *= 2' and it returns Syntax Error

I can get the add and multiplication to run just fine with **mul** and **rmul** , it is the **imul** that has stumped me on this question.

The Exercise Question reads: Challenge Task 2 of 2

Now wrap it up by adding in **imul**, which does in-place multiplication. Be sure to update self.value!

My Answer: / problem code reads:

```
class NumString:
def __mul__(self, other):
if '.' in self.value:
return float(self) * other
return int(self) * other
def __rmul__(self, other):
self.value = self * other
return self.value
def __imul__(self, other):
self.value = self.value * other
return self.value
```

The returned error is:

```
>>> from numstring import NumString
>>> NumString(3) *= 2
File "<stdin>", line 1
SyntaxError: can't assign to function call
>>>
```

Can anyone help? Thankyou :)

```
class NumString:
def __init__(self, value):
self.value = str(value)
def __mul__(self, other):
if '.' in self.value:
return float(self) * other
return int(self) * other
def __rmul__(self, other):
self.value = self * other
return self.value
def __imul__(self, other):
self.value = self * other
return self.value
def __str__(self):
return self.value
def __int__(self):
return int(self.value)
def __float__(self):
return float(self.value)
def __add__(self, other):
if '.' in self.value:
return float(self) + other
return int(self) + other
def __radd__(self, other):
return self + other
def __iadd__(self, other):
self.value = self + other
return self.value
```

## 1 Answer

###### Chris Freeman

Treehouse Moderator 68,064 PointsThe function call `NumString(3)`

used to create the instance cannot be on the left side of a iterative statement. Break it in two statements give you:

```
# Using simple multiply works
>>> NumString(3)
<NumString object at 0x7f5df4f58a20>
>>> NumString(3) * 3
9
# but iterative multiply fails because this:
>>> NumString(3) *= 3
# is the same as
>>> NumString(3) = NumString(3) * 3
# Breaking it in two parts works:
>>> ns = NumString(3)
>>> ns
<imul.NumString object at 0x7f5df4f58a20>
>>> print(ns)
3
>>> ns *= 3
>>> ns
'333'
```

The result is `'333'`

because a string times an integer *n* returns the string repeated *n* times. If you wish to preserve the class, you will need to figure out how to multiply as numbers, then reassign `self.value`

as a string. Lastly, remember to **return self**

Post back if you need more help. Good luck!!

## Steven Hender

5,830 Points## Steven Hender

5,830 PointsThankyou :) All good! This makes sense!