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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 build(template_directories):
 """ Build a template from the source template directories. :param template_directories: source template directories :return: template workflow """

    template = load_template(template_directories[0])
    for directory in template_directories[1:]:
        template.update(load_template(directory))
    return template