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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 _add_fragment(cls, syncmap, identifier, lines, begin, end, language=None):
 """ Add a new fragment to ``syncmap``. :param syncmap: the syncmap to append to :type syncmap: :class:`~aeneas.syncmap.SyncMap` :param identifier: the identifier :type identifier: string :param lines: the lines of the text :type lines: list of string :param begin: the begin time :type begin: :class:`~aeneas.exacttiming.TimeValue` :param end: the end time :type end: :class:`~aeneas.exacttiming.TimeValue` :param language: the language :type language: string """

        syncmap.add_fragment(
            SyncMapFragment(
                text_fragment=TextFragment(
                    identifier=identifier,
                    lines=lines,
                    language=language
                ),
                begin=begin,
                end=end
            )
        )