Python-selenese is a small lib to execute selenese HTML files on a python selenium WebDriver:
from selenium.webdriver.chrome.webdriver import WebDriver
from selenese import TestRunner
testrunner = TestRunner.from_file('my_testcase.html')
results = testrunner.run()
The main benefit for using selenese is the ability to use the Selenium-IDE and that test cases are stored as HTML files and not as source code. So it is easy for non-developers to create test cases and the test cases can be executed without security considerations.
The HTML selenese files can be executed on every selenium WebDriver, which means that the selenese test cases can be executed on every browser and can be scheduled in parallel, both not possible with the Selenium IDE.