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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 format_keyword(keyword):
 """ Removing special character from a keyword. Analysis Services must have this kind of keywords. E.g. if assay name from the Instrument is 'HIV-1 2.0', an AS must be created on Bika with the keyword 'HIV120' """

    import re
    result = ''
    if keyword:
        result = re.sub(r"\W", "", keyword)
        result = re.sub("_", "", result)
    return result