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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 parse_unit(expression):
 """Evaluate a python expression string containing constants Argument: | ``expression`` -- A string containing a numerical expressions including unit conversions. In addition to the variables in this module, also the following shorthands are supported: """

    try:
        g = globals()
        g.update(shorthands)
        return float(eval(str(expression), g))
    except:
        raise ValueError("Could not interpret '%s' as a unit or a measure." % expression)