This was an issue in the old days when you get your GDS layout form
a digital place and route tool which took the Verilog bus naming
convention [ and you streamed it in to Cadence DFII.
There is an option in your stream interface today
in PIPO 'Replace [ with <>',
XStream, should do this automatically,
but I'm not sure here (maybe some other can comment).
There is on old discussion in comp.cad.cadence about this,
which answres every question, 'Titel: A seemingly simple Skill question ...'
There is also a SourceLink Solution which offers the reverse way
You have modify the code to your needs.