Python string (password) generator (few examples)

app.py

# 1st
import string
import random

def pw_gen(size = 8, chars=string.ascii_letters + string.digits + string.punctuation):
	return ''.join(random.choice(chars) for _ in range(size))

print(pw_gen(int(input('How many characters in your password?'))))

#2nd
# generate a password with length "passlen" with no duplicate characters in the password

import random

s = "abcdefghijklmnopqrstuvwxyz01234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ!@#$%^&*()?"
passlen = 8
p =  "".join(random.sample(s,passlen ))
print p

#3rd
import string
import random

def passwordGenerator(): 
	return "".join([string.printable[random.randint(0,len(string.printable)-1)] for i in range(random.randint(8,12))])
print passwordGenerator()

password_generator.py

import random

#setup required variables 

lower_letters = "abcdefghijklmnopqrstuvwxyz"
upper_letters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
symbols = "!@_$%^&"

pass_len = int(raw_input("The required password length is: "))
upper_len = int(raw_input("The required number of upper case letters is: "))
symb_len = int(raw_input("The required number of symbols is: "))
num_len = int(raw_input("The required number of numbers is: "))

num_lower = pass_len - upper_len - symb_len - num_len

pw_list = []

if num_lower < 0:
	print("Sorry, the numbers you entered don't match up! Please try again ...")
	exit()
	
	
#insert lowercase letters
i = 0

while i < num_lower:
	pw_list.append(str(''.join(random.sample(lower_letters, 1))))
	i += 1

	
#insert uppercase 
j = 0
upper_inc = num_lower - 1

while j < upper_len:
	pw_list.insert(random.randint(0, upper_inc), str(''.join(random.sample(upper_letters, 1))))
	j += 1
	upper_inc += 1

	
#insert symbols 
k = 0
symbol_inc = num_lower + upper_len - 1

while k < symb_len:
	pw_list.insert(random.randint(0, symbol_inc), str(''.join(random.sample(symbols, 1))))
	k += 1
	symbol_inc += 1

	
#insert numbers 
l = 0
num_inc = num_lower + upper_len + symb_len - 1

while l < num_len:
	pw_list.insert(random.randint(0, num_inc), str(random.randint(0, 9)))
	l += 1
	symbol_inc += 1

	
#print password	
print("Your generated password is: " + str(''.join(pw_list)))