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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 current_context():
 """Returns the current context. By default, `mx.cpu()` is used for all the computations and it can be overridden by using `with mx.Context(x)` statement where x can be cpu(device_id) or gpu(device_id). Examples ------- cpu(0) gpu(1) cpu(0) Returns ------- default_ctx : Context """

    if not hasattr(Context._default_ctx, "value"):
        Context._default_ctx.value = Context('cpu', 0)
    return Context._default_ctx.value