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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 get(gandi, g, key):
 """Display value of a given config key."""

    val = gandi.get(key=key, global_=g)
    if not val:
        gandi.echo("No value found.")
        sys.exit(1)
    gandi.echo(val)