def match_extensions(self, filename):
        myext = os.path.splitext(filename)[1].lower().lstrip(".")
        result = []
        if len(myext) > 0:
            for element in self.formats:
                if element.findall('extension') != None:
                    for format in element.findall('extension'):
                        if myext == format.text:
                            result.append((element, self.externalsig))
                            break
        result = [match for match in result if self.as_good_as_any(match[0], result)]
        return result
Return the list of (format, self.externalsig) for every format whose extension matches the filename.
dataset/ETHPy150Open openpreserve/fido/fido/fido.py/Fido.match_extensions