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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 prefer_gpu():
 """Use GPU if it's available. Returns True if so, False otherwise."""

    from ._classes.model import Model
    from .ops import CupyOps

    if CupyOps.xp is not None:
        Model.Ops = CupyOps
        Model.ops = CupyOps()
        return True
    else:
        return False