input: Write a function to filter a list of integers and return only those that are greater than 50 using a lambda expression.
  
  function_header:
  assert filter_greater_than_50([45, 12, 52, 89, 33, 99])==[52, 89, 99]
  assert filter_greater_than_50([10, 20, 30, 55, 60, 70])==[55, 60, 70]
  assert filter_greater_than_50([50, 50, 50])==[]
  assert filter_greater_than_50([])==[]
  assert filter_greater_than_50([60, 70, 80])==[60, 70, 80]
output: return list(filter(lambda x: x > 50, lst))