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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 template(tpl, template_adapter=SimpleTemplate, **kwargs):
    '''
    Get a rendered template as a string iterator.
    You can use a name, a filename or a template string as first parameter.
    '''
    if tpl not in TEMPLATES or DEBUG:
        settings = kwargs.get('template_settings',{})
        lookup = kwargs.get('template_lookup', TEMPLATE_PATH)
        if isinstance(tpl, template_adapter):
            TEMPLATES[tpl] = tpl
            if settings: TEMPLATES[tpl].prepare(settings)
        elif "\n" in tpl or "{" in tpl or "%" in tpl or '$' in tpl:
            TEMPLATES[tpl] = template_adapter(source=tpl, lookup=lookup, settings=settings)
        else:
            TEMPLATES[tpl] = template_adapter(name=tpl, lookup=lookup, settings=settings)
    if not TEMPLATES[tpl]:
        abort(500, 'Template (%s) not found' % tpl)
    kwargs['abort'] = abort
    kwargs['request'] = request
    kwargs['response'] = response
    return TEMPLATES[tpl].render(**kwargs)