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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 import_sanitizer(sanitizer):
 """ Imports the sanitizer python module. :param sanitizer: Sanitizer python module file. :type sanitizer: unicode :return: Module. :rtype: object """


    directory = os.path.dirname(sanitizer)
    not directory in sys.path and sys.path.append(directory)

    namespace = __import__(foundations.strings.get_splitext_basename(sanitizer))
    if hasattr(namespace, "bleach"):
        return namespace
    else:
        raise foundations.exceptions.ProgrammingError(
            "{0} | '{1}' is not a valid sanitizer module file!".format(sanitizer))