Problem
Suppose that an employee record consists of an employee's name (a string), age (an integer), gender (female or male), and grade (managerial, clerical, or manual). You are given employees, a list of employee records. Write list comprehensions to compute the following:
(a) a list of all female employees;
(b) a list of all male employees over 60 years of age;
(c) a list of the names of all managers. Also write an expression to compute
(d) the mean age of all female clerical employees.