A script to check if the password is secure. Contains 4 separate functions. Only checks for lower case upper case and numbers but u can also add symbols very easily.

ispasswd.py

#! /bin/python3

'''
WRITTEN BY TUSHAR MAHARANA @tusharhero.github.io
Took 4 days pls do link me if you use this(highly unlikely)
have fun!
'''

'''
LICENSE: https://tusharhero.mit-license.org/
'''
#A python function to check whether a password is secure.
#It checks for the following criteria: atleast 8 characters , lower case, higher case, and numbers
def lengthchk(s,l): #function to check if the length of the password is atleast 8
    l = l - 1
    if len(s) >= l:
        return 1
    else:
        return 0



def isit(l,dic):# function to check if it atleast contains 1 character from the string
    n = 0 #will be used to looping through the string 'dic'
    tt = 0 #will also be used for looping through the string 'dic'
    for tt in dic: # checks for the 'tt' th letter
        if tt == l: #if equals our input then return 1
            return 1
        else:
            n = n + 1 #using this variable because tt is a string now and we need to convert it to a int so we can continue the next loop
            tt = n
    return 0



def isstring(s,dic):# function to check to if the string countains any character from the string uses isit() 
    s = str(s)#just to make sure it's a string
    a = 0 # will be xplained when used
    l = 0 # will be xplained when used
    while l < len(s): #will loop until every charater is used up and l is used to keep track of the characters
        a = isit(s[l],dic) # uses the isit()  to check if the 'l'th character is a valid character
        if a == 1: # if it is then returns 1
            return 1
        else:# if not just continue
            l = l + 1  # keeping track of the character number
    return 0 # if it still doesn't return 1 and the loop finishes then it returns 0 because nothing matched

def ispasswd(passwd,l,h,n,length):#combines all the functions to check if a password is valid
    if lengthchk(passwd,length) == 1:#check if lenghth is correct
        if isstring(passwd,l):#check if l is in the password
            if isstring(passwd, h):#check if h is in the password
                if isstring(passwd, n):#check if n is in the password
                    return 1#finally return 1
                else:#igonre this confusing code i will fix it in the future
                    return 0
            else:
                return 0
        else:
            return 0
    else:
        return 0




#driver code
lowercase = 'abcdefghijklmnopqrstuvwxyz'
highercase = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
num =  '1234567890'#string containing all lower letters, all numbers, higher letters 
print(ispasswd('Amogussussybaka69', lowercase,highercase,num, 8))


#Archived code.
#funny fails
'''
def ispasswd(passwd,dic,l):#combines all the functions to check if a password is valid
    if lengthchk(passwd,l) == 1:#check if lenghth is correct
        if isstring(passwd,dic):#check if characters from dic is in the password
            return 1
        else: #if no
            return 0
    else:#if not
        return 0

def ispasswd(passwd,l,h,n,length):#combines all the functions to check if a password is valid
    if lengthchk(passwd,length) == 1:#check if lenghth is correct
        if isstring(passwd,l):#check if l is in the password
            if isstring(passwd, h):#check if h is in the password
                if isstring(passwd, n):#check if n is in the password
                    return 1#finally return 1
                else:#igonre this confusing code i will fix it in the future
                    return 0
            else:
                return 0
        else:
            return 0
    else:
        return 0


#driver code
l = 'abcdefghijklmnopqrstuvwxyz' #string containing all lower letters
h = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' #string containing all higher letters 
n = '1234567890'#string containing all higher letters letters
print(ispasswd('12345Ba', l, h, n, 8))

def islower(l):
    low = 'abcdefghijklmnopqrstuvwxyz'
    a = 0
    b = 0
    while b == 0:
        if l == low[b:]:
            a = 1
        else:
            a = 0
        b = b + 1
    return 1
#'''

'''
def islower(l):
    low = 'abcdefghijklmnopqrstuvwxyz'
    for l in low[:1]:
        return 1
    else:
        return 0
#'''

I fixed that problem

Added input feature

https://gist.github.com/biologyscience/906469cb3ae853c8a9de34ee4a4c981f