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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def save_source(driver, name):
 """ Save the rendered HTML of the browser. The location of the source can be configured by the environment variable `SAVED_SOURCE_DIR`. If not set, this defaults to the current working directory. Args: driver (selenium.webdriver):
 The Selenium-controlled browser. name (str):
 A name to use in the output file name. Note that ".html" is appended automatically Returns: None """

    source = driver.page_source
    file_name = os.path.join(os.environ.get('SAVED_SOURCE_DIR'),
                             '{name}.html'.format(name=name))

    try:
        with open(file_name, 'wb') as output_file:
            output_file.write(source.encode('utf-8'))
    except Exception:  # pylint: disable=broad-except
        msg = u"Could not save the browser page source to {}.".format(file_name)
        LOGGER.warning(msg)