if a string starts with 'New: ',new message is starting : input_arr = [
    "New: Hello",
    "How are",
    "you",
    "New: I am",
    "fine"
]
def merge_messages(input_arr):
      #don't know that to do here
  return input_arr

print(merge_messages(input_arr))


#Expected Output

[

"New: Hello How are you",

"New: I am fine"

]