docs: def import_private_key(self, pem_text, password=None):
  		""" Import a private key from data in PEM-format
  
  		:param pem_text: text with private key
  		:param password: If it is not None, then result will be decrypt with the given password
  		:return: None
  		"""
  		if isinstance(pem_text, str) is True:
  			pem_text = pem_text.encode()
  		if password is not None and isinstance(password, str) is True:
  			password = password.encode()
  
  		self.__set_private_key(
  			serialization.load_pem_private_key(pem_text, password=password, backend=default_backend())
  		)