```
In [1]:
```from math import pi, sin

The above expression brings in **pi** and **sin** from the math library.

```
In [2]:
```pi # The constant pi

```
Out[2]:
```

```
In [3]:
```sin(pi*1/2.) # The function sin

```
Out[3]:
```

You can also just import a library and not any particular function.

```
In [4]:
```import math
math.e

```
Out[4]:
```

```
In [5]:
```import math as m
m.e

```
Out[5]:
```