old_contents: l = list((1, 2, 3, 4, 5))
  l2 = list(range(10))
  l3 = [-1, -2, -3, -4]
  
  print("List => %r List2 => %r List3 => %r" %(l, l2, l3))
  
  filtered_list = list(filter(lambda num: num % 2 == 0, l2))
  
  print(filtered_list)
  
  
  
new_contents: #list
  l = list((1, 2, 3, 4, 5))
  l2 = list(range(10))
  l3 = [-1, -2, -3, -4]
  
  print("List => %r List2 => %r List3 => %r" %(l, l2, l3))
  
  filtered_list = list(filter(lambda num: num % 2 == 0, l2))
  
  print(filtered_list)
  
  print(l[0])
  
  print(l[1:4])
  
  tup_list = list((("key", "value"), ("key1", "value1")))
  for k, v in tup_list:
      print(k, "->", v)
  
  #set
  colors = set(("red", "green", "blue"))
  for c in colors:
      print(c)
  
  #dict
  d = dict()
  d["key"] = "value"
  d["key1"] = "value1"
  for key in d.keys():
      print(d[key])
  
  #tuple
  t = ("a", 1, "c")
  print(t[2])
subject: Add collection demos.