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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 _diff_group(group):
 """Generate a diff section for diff group"""

    yield _diff_group_position(group)

    for old_line, new_line, line_or_conflict in group:
        if isinstance(line_or_conflict, tuple):
            old, new = line_or_conflict
            for o in old:
                yield color.Deleted('-' + o.strip('\n'))

            if new and old and new[-1].endswith('\n') and not old[-1].endswith('\n'):  # new last line has a newline but old last line doesn't
                yield "\ No newline at end of file"

            for n in new:
                yield color.Added('+' + n.strip('\n'))

            if old and new and old[-1].endswith('\n') and not new[-1].endswith('\n'):  # old last line has a newline but new last line doesn't
                yield "\ No newline at end of file"

        else:
            yield ' ' + line_or_conflict.strip('\n')