Parse the next event from the current file position

def _create_blob(self):
        """Parse the next event from the current file position"""
        blob = None
        for line in self.blob_file:
            line = try_decode_string(line)
            line = line.strip()
            if line == '':
                self.log.info("Ignoring empty line...")
                continue
            if line.startswith('end_event:') and blob:
                blob['raw_header'] = self.raw_header
                return blob
            try:
                tag, values = line.split(':')
            except ValueError:
                self.log.warning("Ignoring corrupt line: {}".format(line))
                continue
            try:
                values = tuple(split(values.strip(), callback=float))
            except ValueError:
                self.log.info("Empty value: {}".format(values))
            if line.startswith('start_event:'):
                blob = Blob()
                blob[tag] = tuple(int(v) for v in values)
                continue
            if tag not in blob:
                blob[tag] = []
            blob[tag].append(values)