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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 keys_values(data, *keys):
 """Get an entry as a list from a dict. Provide a fallback key."""

    values = []
    if is_mapping(data):
        for key in keys:
            if key in data:
                values.extend(ensure_list(data[key]))
    return values