Learning Python

I started taking the Python Essential Training course from LinkedIn Learning. The challenges are getting harder and harder, but I managed to do them without any help. The codes I made were not the most efficient ones, but at least they did the jobs. Below are the codes I made for each challenge:

Description	Code
Factorial Gets the factorial of any integer.	def factorial(num): if type(num) == int: if num >= 0: i = 1 result = 1 while i < num: i +=1 result = result * i print(result) else: print(None) else: print(None) factorial(3)
Hex to decimal converter Converts hexadecimal strings to decimals.	def hexToDec(hexNum): valid = True result = 0 a = 0 for item in hexNum: if not item in hexNumbers: valid = False if not valid: print(None) else: for item in hexNum: a += 1 result = result + 16**(len(hexNum)-a)*hexNumbers[item] print(result) hexToDec('ABC')
ASCII Art Compressor/Decompressor Converts ASCII art to a list of tuples, and unpacks the output.	def encodeString(stringVal): testFinal = [] for a in testList: index = 0 count = 1 testLine = [] for i in a: index += 1 if index < len(a): if i == a[index]: count += 1 else: testLine.append((i,count)) count = 1 else: testLine.append((i,count)) testFinal.append(testLine) print(testFinal) def decodeString(encodedList): for a in testFinal: dstring = '' for (char,dcount) in a: dstring = dstring + (char*dcount) print(dstring)
Prime Numbers Until Entered Number Gets all the prime numbers up to the square root of the entered number, then gets all numbers that are not divisible by those prime numbers up to the entered number.	def allPrimesUpToTest(num): primesUntilSR = [] for a in range(2, (int(num**0.5) + 1)): for b in range(2, int(a ** 0.5) + 1): if a % b == 0: break else: primesUntilSR.append(a) for c in range(2,num): for d in set(primesUntilSR): if c % d == 0: break else: primesUntilSR.append(c) break for e in set(primesUntilSR): print(e)
Chance to return data A function that has a chance to return data. If data is not returned, the function recurs until data is returned. If recursions exceed the max retries, then the function notifies the user that the server is down.	servicesAreUp = True maxretries = 30 def getData50(): time.sleep(.1) if servicesAreUp and random.random() < 0.5: return 'You got the data! That only happens 50% of the time!' def getData25(): time.sleep(.1) if servicesAreUp and random.random() < 0.25: return 'You got the data! That only happens 25% of the time!' def getData10(): time.sleep(.1) if servicesAreUp and random.random() < 0.1: return 'You got the data! That only happens 10% of the time!' def getWithRetry(dataFunc,retries=0): a = dataFunc() if not a: print(f'Retrying. Total retries: {retries}') retries += 1 if retries <= maxretries: getWithRetry(dataFunc,retries) else: print('Servers are down!') pass else: print(a) getWithRetry(getData50) getWithRetry(getData25) getWithRetry(getData10)
Message Listeners Classes that can collect the timestamps of when messages are sent, and print out the entire list of messages received.	from datetime import datetime def getCurrentTime(): return datetime.now().strftime("%m-%d-%Y %H:%M:%S") class Messenger: def __init__(self, listeners=[]): self.listeners = listeners def send(self, message): for listener in self.listeners: listener.receive(message) def receive(self, message): # Must be implemented by extending classes listener.receiveMessage(message) class SaveMessages(Messenger): def receiveMessage(self, message): listener.listeners.append(((len(listener.listeners)+1),message,datetime.now().strftime("%m-%d-%Y %H:%M:%S"))) def printMessages(self): return listener.listeners # Run this cell after you've written your solution listener = SaveMessages() sender = Messenger([listener]) sender.send('Hello, there! This is the first message') # Run this cell after you've written your solution sender.send('Oh hi! This is the second message!') # Run this cell after you've written your solution sender.send('Hola! This is the third and final message!') listener.printMessages()
Custom Errors Code that captures errors and returns custom messages.	from datetime import datetime def getCurrentTime(): return datetime.now().strftime("%m-%d-%Y %H:%M:%S") class Messenger: def __init__(self, listeners=[]): self.listeners = listeners def send(self, message): for listener in self.listeners: listener.receive(message) def receive(self, message): pass # 1. Finish creating the TooManyMessagesException class class TooManyMessagesException(Exception): pass class SaveMessages(Messenger): def __init__(self, listeners=[]): super().__init__(listeners) self.messages = [] self.max_messages = 15 def receive(self, message): print(message) if len(self.messages) >= self.max_messages: #2. Raise a TooManyMessagesException exception here raise TooManyMessagesException('Too many messages!') self.messages.append({'message': message, 'time': getCurrentTime()}) def printMessages(self): for m in self.messages: print(f'Message: "{m["message"]}" Time: {m["time"]}') self.messages = [] print('Message cache has been cleared') print(self.messages) listener = SaveMessages() sender = Messenger([listener]) # 3. Catch a TooManyMessagesException and print the messages for i in range(0, 30): sender.send(f'This is message {i}') listener.printMessages()