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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 serialize_upload(name, storage, url):
 """ Serialize uploaded file by name and storage. Namespaced by the upload url. """

    if isinstance(storage, LazyObject):
        # Unwrap lazy storage class
        storage._setup()
        cls = storage._wrapped.__class__
    else:
        cls = storage.__class__
    return signing.dumps({
        'name': name,
        'storage': '%s.%s' % (cls.__module__, cls.__name__)
    }, salt=url)