#compsci #python 

**Lists** are positionally ordered collections of arbitrarily typed objects, and they have no fixed size, and are mutable.

## Properties
Lists support [[Python core data types summary|arbitrary nesting]]

## Operations
Because lists are [[Python core data types summary|sequences]], they support all the operations for strings, with some minor differences.
They still have some of their own operations, too, though:

![[Python List methods]]

### Comprehensions
List comprehensions are a way to derive a new list from an another one, like in this example:
```python
M=[[1,2,3],[4,5,6],[7,8,9]]
col2 = [row[1] for row in M]
# col2 = [2,5,8]
```

In Russian, these are known as [[Python генераторы списков]]

Comprehension syntax in parentheses can also be used to create [[Python generators]], to create sets and dictionaries as well.