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I want to create a nested list with one or more of the below lists of tuples, with the order of the list based on user's preference.

Fruits=[("Apples",2),("Oranges",3),("Pineapples",5)]
Clothes=[("Jeans",10),("Shirts",5),("Dresses",15)]
Pets=[("Dogs",3),("Cats",4),("Turtles",2)]

The order of the nested list will depend on the preference of the user.For instance, if the user prefer pets over clothes over fruits. The list will look like this:

[[("Jeans",10),("Shirts",5),("Dresses",15)],[("Jeans",10),("Shirts",5), 
("Dresses",15)],[("Apples",2),("Oranges",3),("Pineapples",5)]]

The user also have the option of picking only one or two items. For instance, if the user only cares about pet and then clothing (doesn't care about fruits), his/her list will look like this.

[[("Dogs",3),("Cats",4),("Turtles",2)],[("Jeans",10),("Shirts",5), 
("Dresses",15)]]

The user input is a list with the preferences in order. For example:

preference= ["Pets", "Fruits", "Clothing"] # preference list for users who care about pets over fruits over clothing.
 or 
preference= ["Fruits", "Clothing"] # preference list for users who care about fruits over clothing (no regard for pets)

This is how I've tried to tackle the problem. First I create an empty list with a corresponding number of nested list:

empty_list=[ for x in range (len(preferences)]

This creates a place holder for the number of nested list I need. I then run a bunch of conditional statement to pop in one list at the time:

if preference[0]=="Fruits":
 empty_list[0]=Fruits
 if preference[1]=="Clothes":
 empty_list[1]=Clothes
 empty_list[2]=Pets
 elif preference[1]=="Pets":
 empty_list[1]=Pets
 empty_list[2]=Clothes

if preference[0]=="Pets":
 empty_list[0]=Pets
 if preference[1]=="Clothes":
 empty_list[1]=Clothes
 empty_list[2]=Fruits
 elif preference[1]=="Fruits":
 empty_list[1]=Fruits
 empty_list[2]=Clothes

if preference[0]=="Clothes":
 empty_list[0]=Clothes
 if preference[1]=="Pets":
 empty_list[1]=Pets
 empty_list[2]=Fruits
 elif preference[1]=="Fruits":
 empty_list[1]=Fruits
 empty_list[2]=Pets

My solution is inefficient and also causes problem with list assignment out of range if there are only two preference as opposed to three. Is there a more Pythonic way of writing this?

Any tip or guidance is most appreciated.

you should store your data in a dictionary

and then access that dictionary by key

data = dict(
 Fruits=[("Apples",2),("Oranges",3),("Pineapples",5)]
 Clothes=[("Jeans",10),("Shirts",5),("Dresses",15)]
 Pets=[("Dogs",3),("Cats",4),("Turtles",2)]
)

once you have it in a dict you can easily access the values with variables

fruits = "Fruits"
my_fruits = data[fruits]

you can then use a simple list comprehension to capture all of your interests

interests = ["Fruits","Pets"] 
interesting_things = [data[interest] for interest in interests]

interests = ["Fruits","Clothes"]
interesting_things = [data[interest] for interest in interests]

Try this method.

def prefer(preference):
 preference_list = 

 choices = 
 "fruits": [
 ("Apples", 2),
 ("Oranges", 3),
 ("Pineapples", 5)
 ],
 "cloths": [
 ("Jeans", 10),
 ("Shirts", 5),
 ("Dresses", 15)
 ],
 "pets": [
 ("Dogs", 3),
 ("Cats", 4),
 ("Turtles", 2)
 ]
 

 for choice in choices:
 if choice in preference:
 preference_list.insert(preference.index(choice), choices[choice])

 else:
 preference_list.append(choices[choice])


 print(preference_list)

prefer(("fruits", "cloths"))