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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 run_sphinx():
 """Runs Sphinx via it's `make html` command"""

    old_dir = here_directory()
    os.chdir(str(doc_directory()))
    doc_status = subprocess.check_call(['make', 'html'], shell=True)
    os.chdir(str(old_dir))  # go back to former working directory
    if doc_status is not 0:
        exit(Fore.RED + 'Something broke generating your documentation...')