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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 parse(template, delimiters=None):
 """ Parse a unicode template string and return a ParsedTemplate instance. Arguments: template: a unicode template string. delimiters: a 2-tuple of delimiters. Defaults to the package default. Examples: ['Hey ', _SectionNode(key='who', index_begin=12, index_end=21, parsed=[_EscapeNode(key='name'), '!'])] """

    if type(template) is not unicode:
        raise Exception("Template is not unicode: %s" % type(template))
    parser = _Parser(delimiters)
    return parser.parse(template)