/var/lib/pcp/config/pmchart/Netbytes is in pcp-gui 4.0.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | #kmchart
version 1
chart title "Network Interface Bytes [%h]" style stacking
plot legend "in %i" metric network.interface.in.bytes not-matching "^lo|^gif|^sl|^sit|^stf|^tun|^wlt|^virbr|^vnet|^vmnet|^MS TCP Loopback interface"
plot legend "out %i" metric network.interface.out.bytes not-matching "^lo|^gif|^sl|^sit|^stf|^tun|^wlt|^virbr|^vnet|^vmnet|^MS TCP Loopback interface"
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