What does eval do When can it be used?
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# What does eval do When can it be used?

This recipe explains what does eval do When can it be used

## Recipe Objective

Suppose we have a code in form of string and we want to run it replacing values of variables. It can be achieved via eval function.

So this recipe is a short example on What does eval do and When can it be used. Let's get started.

## Step 1 - Import the library

``` import pandas as pd ```

Let's pause and look at these imports. Pandas is generally used for performing mathematical operation and preferably over arrays.

## Step 2 - Setup the Data

``` expression='x*(x+1)*(x+2)' x=4 ```

Here we have setup one string and assigned a constant value to a variable.

## Step 3 - Calculative eval()

``` eval(expression) ```

Simply pass the string expression into eval() function.

## Step 4 - Let's look at our dataset now

Once we run the above code snippet, we will see:

```120
```

Value of x has been simply passed into x for further calculation.

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