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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 build_item( title, key=None, synonyms=None, description=None, img_url=None, alt_text=None ):
 """Builds an item that may be added to List or Carousel"""

    item = {
        "info": {"key": key or title, "synonyms": synonyms or []},
        "title": title,
        "description": description,
        "image": {
            "imageUri": img_url or "",
            "accessibilityText": alt_text or "{} img".format(title),
        },
    }
    return item