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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 get_certifi_file():
 """Get the SSL certifications installed by the certifi package. @return: the filename to the cert file @rtype: string @raises: ImportError when certifi is not installed or ValueError when the file is not found """

    import certifi
    filename = certifi.where()
    if os.path.isfile(filename):
        return filename
    msg = "%s not found; check your certifi installation" % filename
    raise ValueError(msg)