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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 _TemplateExists(unused_value, context, args):
 """Returns whether the given name is in the current Template's template group."""

    try:
        name = args[0]
    except IndexError:
        raise EvaluationError('The "template" predicate requires an argument.')
    return context.HasTemplate(name)