Relevant matters in deciding whether use is fair
191.  Subject to sections 192, 193 and 194, all relevant matters must be considered in deciding whether a work or a protected performance (including a recording of the performance) is fairly used, including —
(a)the purpose and character of the use, including whether the use is of a commercial nature or is for non‑profit educational purposes;
(b)the nature of the work or performance;
(c)the amount and substantiality of the portion used in relation to the whole work or performance; and
(d)the effect of the use upon the potential market for, or value of, the work or performance.