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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(current, desired):
 """ Calculate the conversion from one set of units to another. Parameters --------- current : str Unit system values are in now (eg 'millimeters') desired : str Unit system we'd like values in (eg 'inches') Returns --------- conversion : float Number to multiply by to put values into desired units """

    current = str(current).strip().lower()
    desired = str(desired).strip().lower()
    conversion = TO_INCH[current] / TO_INCH[desired]
    return conversion