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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 format_interface_name(intf_type, port, ch_grp=0):
 """Method to format interface name given type, port. Given interface type, port, and channel-group, this method formats an interface name. If channel-group is non-zero, then port-channel is configured. :param intf_type: Such as 'ethernet' or 'port-channel' :param port: unique identification -- 1/32 or 1 :ch_grp: If non-zero, ignore other params and format port-channel<ch_grp> :returns: the full formatted interface name. ex: ethernet:1/32, port-channel:1 """

    if ch_grp > 0:
        return 'port-channel:%s' % str(ch_grp)

    return '%s:%s' % (intf_type.lower(), port)