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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 config(env=DEFAULT_ENV, default=None, **overrides):
 """Returns configured REDIS dictionary from REDIS_URL."""


    config = {}

    s = os.environ.get(env, default)

    if s:
        config = parse(s)

    overrides = dict([(k.upper(), v) for k, v in overrides.items()])

    config.update(overrides)

    return config