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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 is_storage(url, storage=None):
 """ Check if file is a local file or a storage file. File is considered local if: - URL is a local path. - URL starts by "file://" - a "storage" is provided. Args: url (str):
 file path or URL storage (str):
 Storage name. Returns: bool: return True if file is local. """

    if storage:
        return True
    split_url = url.split('://', 1)
    if len(split_url) == 2 and split_url[0].lower() != 'file':
        return True
    return False