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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 _load_pretrained_tok2vec(nlp, loc):
 """Load pre-trained weights for the 'token-to-vector' part of the component models, which is typically a CNN. See 'spacy pretrain'. Experimental. """

    with loc.open("rb") as file_:
        weights_data = file_.read()
    loaded = []
    for name, component in nlp.pipeline:
        if hasattr(component, "model") and hasattr(component.model, "tok2vec"):
            component.tok2vec.from_bytes(weights_data)
            loaded.append(name)
    return loaded