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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 host(value):
 """ Validates that the value is a valid network location """

    if not value:
        return (True, "")
    try:
        host,port = value.split(":")
    except ValueError as _:
        return (False, "value needs to be <host>:<port>")

    try:
        int(port)
    except ValueError as _:
        return (False, "port component of the host address needs to be a number")

    return (True, "")