input: Write a function to calculate the average salary from a given CSV file containing a list of names and their corresponding salaries. The function should return the average value of the salaries. If the CSV file is empty, the function should return 0.0.
  assert get_average_salary('salary.csv')==2000.0
  assert get_average_salary('empty_salary.csv')==0.0
  assert get_average_salary('new_salary.csv')==5000.0
  assert get_average_salary('partial_salary.csv')==1500.0
  assert get_average_salary('zero_salary.csv')==0.0
output: def get_average_salary(filename):
      try:
          with open(filename, 'r') as file:
              lines = file.readlines()
              if not lines:
                  return 0.0
              total_salary = 0.0
              count = 0
              for line in lines:
                  name, salary = line.strip().split(',')
                  total_salary += float(salary)
                  count += 1
              return total_salary / count if count > 0 else 0.0
      except FileNotFoundError:
          return 0.0