input: Write a python function to check if a file exists on YoupornCom using the provided class.
  assert YoupornCom().file_exists() == True
  assert YoupornCom().file_exists() == False
output: def file_exists(self):
      # Check if the file exists by calling the necessary API or performing the required check
      # For the sake of this example, let's assume we have a method self.check_file() that returns True if the file exists
      return self.check_file()
  
  class YoupornCom:
      def __init__(self):
          # Initialization code if necessary
          pass
  
      def check_file(self):
          # Dummy implementation for example purposes
          # Replace this with actual file checking logic
          return True
  
      def file_exists(self):
          # Check if the file exists
          return self.check_file()