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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 prev_deps(env):
 """Naively gets the dependancies from the last time ctox was run."""

    # TODO something more clever.
    if not os.path.isfile(env.envctoxfile):
        return []

    with open(env.envctoxfile) as f:
        return f.read().split()