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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 _join_host_port(host, port):
 """Adapted golang's net.JoinHostPort"""

    template = "%s:%s"
    host_requires_bracketing = ':' in host or '%' in host
    if host_requires_bracketing:
        template = "[%s]:%s"
    return template % (host, port)