A duplicate block is any section of code over 100 tokens which appears more than once in a repository. A token is counted based on the way code is parsed.
In the following example we break down a statement into 11 tokens, the same way a parser would see it.
example statement a = 3 + b
statement( assignment_expression( left_side( name(a), operand(+), right_side( infix_expression( left_side(int), operand(+), right_side( name(b) ) ) ) ) ) )