regexp using {…} syntactically looks like a list, but must be manually changed

Typically, the Jacl syntax treats {xxxx} or "{xxxx}" as a list. However, if {xxxx} or "{xxxx}" is used in a regexp expression, the Jacl runtime treats it as a String. The token parser of Jacl2Jython program is not context sensitive and cannot handle this situation. As a result, a token parsing error occurs. The solution is that you need to manually modify any regexp{xxxx} expressions into explicit Strings.
JACL:   #regexp {(.*)(\(cells.*)} $x  # will cause parse error
JACL:   regexp "(.*)(\(cells.*)" $x   # manually modified
==>
JYTHON: #regexp {(.*)(\(cells.*)} $x  # will cause parse error 
JYTHON: regexp("(.*)(\(cells.*)", x)  # alternatively, manually corrected
Related reference
Printing a List instead of a String, and printing Objects

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