Verify the Identity Shown Below $$\sec ^ { 2 } \left( \frac { \pi } { 2 } - y \right) - 1 = \cot ^ { 2 } y$$

Essay

Verify the identity shown below. $$\sec ^ { 2 } \left( \frac { \pi } { 2 } - y \right) - 1 = \cot ^ { 2 } y$$