input: Write a function to compute the average salary of people from a CSV file named 'salary.csv' containing 'name' and 'salary' columns. The function should skip the header row and calculate the average of the salary column. If the CSV file is empty or doesn't exist, the function should return 0.
  
  assert get_average_salary('salary.csv')==2000.0
  assert get_average_salary('non_existent_file.csv')==0
  assert get_average_salary('empty_file.csv')==0
output: def get_average_salary(filename):
      try:
          with open(filename, 'r') as file:
              lines = file.readlines()
              if len(lines) <= 1:
                  return 0
              salaries = [float(line.split(',')[1]) for line in lines[1:]]
              return sum(salaries) / len(salaries)
      except (FileNotFoundError, ZeroDivisionError):
          return 0