input: Write a python function to create a UserProfile class with methods to get the username and password.
  assert user.get_username() == 'username'
  assert user.get_password() == 'password'
output: def UserProfile:
      def __init__(self, username, password):
          self._username = username
          self._password = password
  
      def get_username(self):
          return self._username
  
      def get_password(self):
          return self._password
  
  # Example usage
  user = UserProfile('username', 'password')