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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_filter(cls, mimetype):
 """ Returns a filter string for the file dialog. The filter is based on the mime type. :param mimetype: path from which the filter must be derived. :return: Filter string """

        filters = ' '.join(
            ['*%s' % ext for ext in mimetypes.guess_all_extensions(mimetype)])
        return '%s (%s)' % (mimetype, filters)