movies = ["The Holy Grail", 1975, "Terry Jones & Terry Gilliam", 91,
["Graham Chapman",
["Michael Palin", "John Cleese", "Terry Gilliam", "Eric Idle", "Terry Jones"]]]


In the above code, how does [4][1][3] result in "Eric Idle"? It looks to me like the 4 selects Eric Idle becaue it's the 4th sting in that list, it also looks to me like the 3 selects that list because Eric Idle is in the 3rd list and I have no diea what the 1 might be going. And maybe I'M wrong all together.

as I see it it's like this

the checking starts with 0 (list indeces start with 0) so it would look like

movies [ 0 , 1 , 2 , 3 , [ 0 , [ 0 , 1 , 2 , 3 ] ] ]

where the 4th one is a list and inside it the second one is a list

so from left to right [4][1][3] should point to Eric Idle

Edited 4 Years Ago by zeroliken

Bump tot he above poster, it is most certainly better to store variables so they may be accessed by attribute (eg movie.director)

Look at this:

# named tuples have named indexes they behave similar to class
# instances but require no more memory than regular tuples
# the record_list of named tuples can be saved(dumped) and loaded
# with Python module pickle

import collections as co

# create the named tuple
Movies = co.namedtuple('Movies',
         'title, year, director, minutes, cast')

record_list = []
# create one record for the record_list
title = "The Holy Grail"
year = 1975
director = "Terry Jones & Terry Gilliam"
minutes = 91
cast = [
'Graham Chapman',
'John Cleese',
'Terry Gilliam',
'Eric Idle',
'Terry Jones',
'Michael Palin']
record_list.append(Movies(title, year, director, minutes, cast))

# now you can do things like this
actor = 'John Cleese'
for movies in record_list:
    if actor in movies.cast:
        print("%s acted in %s" % (actor, movies.title))

'''my result -->
John Cleese acted in The Holy Grail

Edited 4 Years Ago by Ene Uran: pickel

the way to go

the checking starts with 0 (list indeces start with 0)

Lists don't have indexes, lists use offsets. So "some_list[5]" means offset 5 from the beginning, or skip over the first 5 elements=beginning of the sixth. It comes from the beginning days of computers when programmers had to do everything for themselves. If a list contained fixed length elements and you wanted to start reading from the beginning of the sixth element, you would move the memory or file pointer ahead 5*length-of-element. For example, if the list contained 2 byte integers you would skip over the first 10 bytes and read the next 2. If you want the first element, you would skip 0 bytes, etc. Today, Python takes care of this for you.

Edited 4 Years Ago by woooee

class Movie():

This defines an old style class. A better way would be to have:

class Movie(object):

This is suggested because old style classes don't play well with type and other new Python constructs. E.g.

>>> class A(): pass
>>> type(A())
<type 'instance'>  <--- not good enough
>>> class A(object): pass
>>> type(A())
<class '__main__.A'> <---- now we are talking

Lists don't have indexes

Actually, they do. From the official tutorial:

Like string indices, list indices start at 0, and lists can be sliced, concatenated and so on:

Edited 4 Years Ago by ~s.o.s~

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