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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 clean_slug(self):
 """slug title if is not provided """

        slug = self.cleaned_data.get('slug', None)
        if slug is None or len(slug) == 0 and 'title' in self.cleaned_data:
            slug = slugify(self.cleaned_data['title'])
        return slug