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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 unit_conversion(thing, units, length=False):
 """converts base data between metric, imperial, or nautical units"""

    if 'n/a' == thing:
        return 'n/a'
    try:
        thing = round(thing * CONVERSION[units][0 + length], 2)
    except TypeError:
        thing = 'fubar'
    return thing, CONVERSION[units][2 + length]