Question: I have a list of list, such as

```
T =[[0.10113], [0.56325], [0.02563], [0.09602], [0.06406], [0.04807]]

```

I would like to find the total sum of these numbers.

I am new to python programming, when I try a simple `int(T[1])` conversion, I get error 

```
TypeError: int() argument must be a string or a number, not 'list'

```

I appreciate any input.

Answer: 
You can use [`map`](http://docs.python.org/2/library/functions.html#map) for this:

```
sum(map(sum, T))

```

```

>>> sum(map(sum, T))
0.89816000000000007

```

From the documentation for `map`:

> 
> **map**(function, iterable, ...)
> 
> 
> Apply function to every item of iterable and return a list of the results.
> 
> 
> 

So you are using `map` to total up the inner lists, and then a call to `sum` to total those values for the final answer.

This approach will work if your inner lists contain multiple items.
```
>>> T =[[0.10113], [0.56325], [0.02563], [0.09602], [0.06406], [0.04807]]
>>> sum(x[0] for x in T)
0.8981600000000001

```