file.py - with comments

class File():
  *** A file on your computer *** # This is a docstring - used to describe the class.

  file_count = 0 # This is a class attribute, it is applied to the class, not an instance.

  # Constructor. Runs on initialisation. Default values included.
  def __init__(self, filename = 'no_name', size = 0):
    self.filename = filename # Sets it's own instance filename value to the one passed to it.
    self.size = size
    self.create_time
    self.__access_key # Two _'s defines it as a private attribute which can only be accessed externally through syntax: myFile._File__access_key

  # Sets a custom return string when an instance itself is printed, ie: print(myFile)
  def __str__(self):
    return f'File: {self.filename} - Size: {self.size}'

  # A instance method - it must use 'self' as the first parameter.
  def summarise(self):
    return f'This file has the name: {self.filename} and is {self.size}. It was created at {self.create_time}'

  # two __'s in method name makes it private, for use by other methods in the class only.
  def __private_method(self):
    print("I'm doing something private!")

  # Properties can be used to return read-only versions of a private attribute (ie, a getter)
  @property
  def access_key(self):
    return self.__access.key

  # A setter method is used to allow updating a private attribute, extra protection logic can be added
  @access_key.setter
  def access_key(self, new_access_key):
    if new_access_key == "":
      print("Access key can't be blank")
    else:
      self.__access_key = new_access_key
      print("Access key updated!")

  # A static method is one that is applied to the class itself, not instances. It's called like File.count() and can't use self.
  @staticmethod
  def count():
    return f'There are {file_count} many files on the system.'

file.py - clean

class File():
  *** A file on your computer ***

  file_count = 0

  def __init__(self, filename = 'no_name', size = 0):
    self.filename = filename
    self.size = size
    self.create_time
    self.__access_key

  def __str__(self):
    return f'File: {self.filename} - Size: {self.size}'

  def summarise(self):
    return f'This file has the name: {self.filename} and is {self.size}. It was created at {self.create_time}'

  def __private_method(self):
    print("I'm doing something private!")

  @property
  def access_key(self):
    return self.__access.key

  @access_key.setter
  def access_key(self, new_access_key):
    if new_access_key == "":
      print("Access key can't be blank")
    else:
      self.__access_key = new_access_key
      print("Access key updated!")

  @staticmethod
  def count():
    return f'There are {file_count} many files on the system.'