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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 wind_shear(shear: str, unit_alt: str = 'ft', unit_wind: str = 'kt', spoken: bool = False) -> str: """ Translate wind shear into a readable string Ex: Wind shear 2000ft from 140 at 30kt """

    if not shear or 'WS' not in shear or '/' not in shear:
        return ''
    shear = shear[2:].rstrip(unit_wind.upper()).split('/')  # type: ignore
    wdir = core.spoken_number(shear[1][:3]) if spoken else shear[1][:3]
    return f'Wind shear {int(shear[0])*100}{unit_alt} from {wdir} at {shear[1][3:]}{unit_wind}'