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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 _merge_section(original, to_merge):
 # type: (str, str) -> str """Merge two sections together. Args: original: The source of header and initial section lines. to_merge: The source for the additional section lines to append. Returns: A new section string that uses the header of the original argument and the section lines from both. """

    if not original:
        return to_merge or ''
    if not to_merge:
        return original or ''
    try:
        index = original.index(':') + 1
    except ValueError:
        index = original.index('\n')
    name = original[:index].strip()
    section = '\n  '.join(
        (original[index + 1:].lstrip(), to_merge[index + 1:].lstrip())
    ).rstrip()
    return '{name}\n  {section}'.format(name=name, section=section)