1. A computerized apparatus comprising: a processor; and a testing scenario generator configured to generate an at least one testing scenario associated with a test template; the test template defining a set of one or more testing scenarios for a target computerized system; the test template comprises an at least one repetitive block comprising: a template counter; and a template instruction; wherein the template counter defines a predetermined range of times to interpret the template instruction into a target instruction; said testing scenario generator comprising: a template instruction interpreter configured to determine an at least one target instruction associated with a template instruction; and a repetitive block interpreter for determining an at least one target instruction associated with the at least one repetitive block; said repetitive block interpreter comprising a repetitive determination unit for determining whether to reuse a portion of the at least one target instruction determined by said template instruction interpreter.