def __init__(self):
try:<EOL><INDENT>sp.check_call(<EOL>["<STR_LIT>", "<STR_LIT>"],<EOL>stdout=DEVNULL, stderr=DEVNULL,<EOL>)<EOL><DEDENT>except OSError:<EOL><INDENT>msg = (<EOL>"<STR_LIT>"<EOL>"<STR_LIT>"<EOL>)<EOL>raise NotConfigured(msg)<EOL><DEDENT>try:<EOL><INDENT>sp.check_call(<EOL>[self.pa11y_path, "<STR_LIT>"],<EOL>stdout=DEVNULL, stderr=DEVNULL,<EOL>)<EOL><DEDENT>except OSError:<EOL><INDENT>msg = (<EOL>u"<STR_LIT>"<EOL>).format(path=self.pa11y_path)<EOL>raise NotConfigured(msg)<EOL><DEDENT>
Check to be sure that `pa11y` and `phantomjs` are installed properly.