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How to sort a list of tuples but with one specific tuple being the first?

I'm doing an application to find the best path for a delivery.
The delivery send me his path:
[
('0', '1'),
('1', '2'),
('0', '2'),
('2', '0')
]
... where every pair of numbers is a location and smallest numbers are closer. They also send me their starting point. For example: 2.
I did a function to sort from lower to higher:
def lowToHigh(trajet):
trajet_opti = trajet
print(sorted(trajet_opti))
lowToHigh([
('0', '1'),
('1', '2'),
('0', '2'),
('2', '0')
])
The output is like this:
[('0', '1'), ('0', '2'), ('1', '2'), ('2', '0')]
I need a function who puts the tuple with the starting number first:
def starting_tuple():
starting_number = 2
.
.
.
Which returns something like this:
[('2', '0'), ('0', '1'), ('0', '2'), ('1', '2')]

Sort with a key that adds another tuple element representing whether the list item equals the starting point.
>>> path = [
... ('0', '1'),
... ('1', '2'),
... ('0', '2'),
... ('2', '0')
... ]
>>> sorted(path, key=lambda c: (c[0] != '2', c))
[('2', '0'), ('0', '1'), ('0', '2'), ('1', '2')]
The expression c[0] != '2' will be False (0) for the starting point and True (1) for all others, which will force the starting point to come at the start of the list. If there are multiple starting points, they will be sorted normally relative to each other.

two list integer combine together in python

I am trying to get integers value from a list of specific functions in a two different list and then try to store both list integer with combination of 2nd list integer.
let suppose we have two list,
list1 = ['A(0)','B(1)','C(3)','Z(4)','Z(7)','Z(2)', 'X(3)','X(2)',...]
list2 = ['A(0)','B(1)','C(3)','Z(7)','Z(3)','Z(5)', 'X(11)','X(4)',...]
now only the integer of Z from list1 and list2 will extract and store like this sequence,
Z1 = A(4,7)
Z1 = A(7,3)
Z2 = B(2,5)
first element of list1 and 2nd element of list2 in a sequence.
here is my code which i tried,
for line in list1:
if 'OUTPUT' in line:
print(line.split('Z(')[1].split(')')[0].strip())
for line in list2:
if 'OUTPUT' in line:
print(line.split('Z(')[1].split(')')[0].strip())
here is output
4 7 7 3 2 5
but still i didnt get value like,
Z1 = A(4,7)
Z1 = A(7,3)
Z2 = B(2,5)

def format_list(lst):
new = []
for sub in lst:
open_p = sub.index("(")
close_p = sub.index(")")
letter = sub[:open_p]
number = sub[open_p + 1 : close_p]
new.append((letter, number))
return new
list1 = ["A(0)", "B(1)", "C(3)", "Z(4)", "Z(7)", "Z(2)", "X(3)", "X(2)"]
list2 = ["A(0)", "B(1)", "C(3)", "Z(7)", "Z(3)", "Z(5)", "X(11)", "X(4)"]
lst1 = format_list(list1)
lst2 = format_list(list2)
The above code will format the lists as so:
lst1 = [('A', '0'), ('B', '1'), ('C', '3'), ('Z', '4'), ('Z', '7'), ('Z', '2'), ('X', '3'), ('X', '2')]
lst2 = [('A', '0'), ('B', '1'), ('C', '3'), ('Z', '7'), ('Z', '3'), ('Z', '5'), ('X', '11'), ('X', '4')]
From there, you'll be able to use filter() to find the places in which the numbers differentiate:
different_obj = list(filter(lambda x: x[0][1] != x[1][1], zip(lst1, lst2)))
print(different_obj)
Or if you rather, you don't need to use filter:
different_obj = []
for x, y in zip(lst1, lst2):
if x[1] != y[1]:
different_obj.append((x, y))
outputs:
[(('Z', '4'), ('Z', '7')),
(('Z', '7'), ('Z', '3')),
(('Z', '2'), ('Z', '5')),
(('X', '3'), ('X', '11')),
(('X', '2'), ('X', '4'))]
From there you should be able to organize different_obj to your goal.

How do I take UNIQUE random choice from two lists

I have two lists that defines a card
values = ['A', 'K', 'Q', 'J', '10', '9', '8', '7', '6', '5', '4', '3', '2']
marks = ['spade', 'hearts', 'diamond', 'club']
I want to have 12 unique cards, so my output should look like
('9', 'diamond')
('K', 'hearts')
('Q', 'hearts')
('7', 'spade')
('A', 'diamond')
('3', 'diamond')
('Q', 'diamond')
('3', 'hearts')
('7', 'hearts')
('2', 'diamond')
('2', 'hearts')
('5', 'spade')
I have used random choice to get this far, my code is here
count = 0
while count != 12:
value = random.choice(values)
mark = random.choice(marks)
card = Card(value, mark)
# I have a class named Card, generate() returns a tuple of mark and value for card
print(card.generate())
count += 1
But it does not provide me unique values. Please let me know or through me a resource to learn how to get unique value by random choice from two lists.

First, combine the marks and values to actual cards using itertools.product, then just random.shuffle the stack of cards and pop cards into the player's hand, like you would in real life.
import itertools, random
cards = list(itertools.product(values, marks))
random.shuffle(cards)
hand = [cards.pop() for _ in range(12)]
At the same time, this will remove the cards from the stack, and thus ensure that cards are unique across the different players' hands. If you do not want this, use random.sample instead. This way, cards are unique within one hand, but not across hands, as they remain in the stack (in this case, the shuffle step is not needed, either):
hand = random.sample(cards, 12)

What i would recommend is using random.sample(population, k) this will return a unique k items from the list population.
However for this you first need to make all the cards and then have all the cards in the list population.
Another solution would be to add a list chosen_cards and implement an equals funcion and do a check in the chosen_cards before you add the new random card to the chosen_cards.

You can do:
cards = [(v, m) for (v, m) in zip(values * 4, marks * 13)]
random.sample(cards, 12)
# RESULT
[('K', 'diamond'),
('K', 'spade'),
('3', 'spade'),
('6', 'hearts'),
('10', 'spade'),
('9', 'hearts'),
('3', 'club'),
('8', 'hearts'),
('Q', 'spade'),
('Q', 'hearts'),
('6', 'club'),
('J', 'diamond')]

How to create value pairs with lambda in pyspark?

I am trying to convert a pyspark rdd like this:
before:
[
[('169', '5'), ('2471', '6'), ('48516', '10')],
[('58', '7'), ('163', '7')],
[('172', '5'), ('186', '4'), ('236', '6')]
]
after:
[
[('169', '5'), ('2471', '6')],
[('169', '5'),('48516', '10')],
[('2471', '6'), ('48516', '10')],
[('58', '7'), ('163', '7')],
[('172', '5'), ('186', '4')],
[('172', '5'), ('236', '6')],
[('186', '4'), ('236', '6')]
]
The idea is to go through each line and create new line pairwise. I tried to find out a solution myself with lambda tutorials but with no good. May I ask for some help? If this is repeating other questions, I apologize. Thanks!

I'd use flatMap with itertools.combinations:
from itertools import combinations
rdd.flatMap(lambda xs: combinations(xs, 2))

Why am I not getting the result of sorted function in expected order?

print activities
activities = sorted(activities,key = lambda item:item[1])
print activities
Activities in this case is a list of tuples like (start_number,finish_number) the output of the above code according to me should be the list of values sorted according the the increasing order of finish_number. When I tried the above code in shell I got the following output. I am not sure why the second list is not sorted according the the increasing order of the finish_number. Please help me in understanding this.
[('1', '4'), ('3', '5'), ('0', '6'), ('5', '7'), ('3', '9'), ('5', '9'), ('6', '10'), ('8', '11'), ('8', '12'), ('2', '14'), ('12', '16')]
[('6', '10'), ('8', '11'), ('8', '12'), ('2', '14'), ('12', '16'), ('1', '4'), ('3', '5'), ('0', '6'), ('5', '7'), ('3', '9'), ('5', '9')]

You are sorting strings instead of integers: in that case, 10 is "smaller" than 4. To sort on integers, convert it to this:
activites = sorted(activities,key = lambda item:int(item[1]))
print activities
Results in:
[('1', '4'), ('3', '5'), ('0', '6'), ('5', '7'), ('3', '9'), ('5', '9'), ('6', '10'), ('8', '11'), ('8', '12'), ('2', '14'), ('12', '16')]

Your items are being compared as strings, not as numbers. Thus, since the 1 character comes before 4 lexicographically, it makes sense that 10 comes before 4.
You need to cast the value to an int first:
activities = sorted(activities,key = lambda item:int(item[1]))

You are sorting strings, not numbers. Strings get sorted character by character.
So, for example '40' is greater than '100' because character 4 is larger than 1.
You can fix this on the fly by simply casting the item as an integer.
activities = sorted(activities,key = lambda item: int(item[1]))

It's because you're not storing the number as a number, but as a string. The string '10' comes before the string '2'. Try:
activities = sorted(activities, key=lambda i: int(i[1]))

Look for a BROADER solution to your problem: Convert your data from str to int immediately on input, work with it as int (otherwise you'll be continually be bumping into little problems like this), and format your data as str for output.
This principle applies generally, e.g. when working with non-ASCII string data, do UTF-8 -> unicode -> UTF-8; don't try to manipulate undecoded text.