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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 create_seq(self, project):
 """Create and return a new sequence :param project: the project for the sequence :type deps: :class:`jukeboxcore.djadapter.models.Project` :returns: The created sequence or None :rtype: None | :class:`jukeboxcore.djadapter.models.Sequence` :raises: None """

        dialog = SequenceCreatorDialog(project=project, parent=self)
        dialog.exec_()
        seq = dialog.sequence
        return seq