#!/usr/bin/env python
#

[SNIPPET_NAME: Lists 101]
[SNIPPET_CATEGORIES: Python Core]
[SNIPPET_DESCRIPTION: Basic and not so basic list operations]
[SNIPPET_AUTHOR: Bruno Girin <brunogirin@gmail.com>]
[SNIPPET_LICENSE: GPL]
This snippet demonstrates how the basics on lists: how to create, add,
remove items, get items or slices, sort, etc.
#
First, let's create simple list
#
print "Create a simple list"
simpleList = ["Karmic", "Lucid", "Hardy", "Jaunty", "Intrepid"]
print it
print simpleList
#
Interrogate the list
#
print "\nInterrogate the list"
get item 3:  lists start counting at 0 so it should be Jaunty
print simpleList[3]
we can also get a slice
print simpleList[2:4]
get the first three items
print simpleList[:3]
or all items from number index 3 (which is the fourth item) to the end
print simpleList[3:]
we can also take every other item, as a slice is defined
like this: start:stop:step
print simpleList[::2]
get the length of the list
print len(simpleList)
we can get the index of an item in the list
print simpleList.index("Hardy")
and when the list doesn't contain the item, we get an error that we can catch
try:
    print simpleList.index("Feisty")
except ValueError:
    print "The list doesn't contain the item Feisty"
#
Modify the list
#
print "\nModify the list"
add another item
simpleList.append("Twisty")
print simpleList
oops! let's sort this out by replacing in place
simpleList[5] = "Gutsy"
print simpleList
extend the list with another one
otherList = ["Edgy", "Breezy"]
simpleList.extend(otherList)
print simpleList
remove an item from the list (Hardy should not be in the list anymore)
del simpleList[2]
print simpleList
insert an item in the middle of the list
simpleList.insert(4, "Hardy")
print simpleList
remove an item by its value rather than its index
simpleList.remove("Edgy")
print simpleList
#
Create modified copies of the list
#
print "\nCreate modified copies of the list"
sort it
print sorted(simpleList)
join it to produce a custom print
print ' => '.join(sorted(simpleList))
lists can contain the same item several times so if we add Lucid again:
simpleList.append("Lucid")
we have it twice in the list (easier to see if we sort it)
print sorted(simpleList)
but we can get round that by transforming it into a set, which is a list
with no duplicates; and of course we can also sort the set
print sorted(set(simpleList))
#
Iterate over the list
#
print "\nIterate over the list"
for i in simpleList:
    print i.upper()
but if we want to create another list by applying the same expression to
each item, we can use a list comprehension
upList = [i.upper() for i in sorted(set(simpleList))]
print upList
 </pre>