Use HR databse and Write a PL/SQL script that creates a user defined function which calculates the total number of employees working at a location in the country 'Canada'. Consider the "Country" as argument to be sent during the function call at rum time. Also write the appropriate call to print the returned value.

DEPARTMENTS * DEPARTMENT_ID * DEPARTMENT_NAME MANAGER_ID LOCATION_ID P LOCATIONS LOCATION_ID STREET_ADDRESS POSTAL_CODE F F F * CITY * JOB_HISTORY PF * EMPLOYEE_ID P START_DATE * END_DATE F* JOB_ID F DEPARTMENT_ID STATE_PROVINCE COUNTRY_ID F EMPLOYEES P * EMPLOYEE_ID FIRST_NAME * LAST_NAME U * EMAIL PHONE_NUMBER HIRE_DATE F* JOB_ID SALARY COMMISSION_PCT F MANAGER_ID F DEPARTMENT_ID V COUNTRIES P * COUNTRY_ID COUNTRY_NAME F REGION_ID V JOBS * JOB_ID JOB_TITLE MIN_SALARY MAX_SALARY REGIONS P * REGION_ID REGION_NAME