from sys import argv


script, input_file = argv



def print_all(f):
print(f.read())



def rewind(f):
f.seek(0)



def print_a_line(line_count, f):
print(line_count, f.readline())


current_file = open(input_file)


print("First let's print the whole file:\n")


print_all(current_file)


print("Now let's rewind, kind of like a tape.")


rewind(current_file)


print("Let's print three lines:")

current_line = 1
print_a_line(current_line, current_file)

current_line = current_line + 1
print_a_line(current_line, current_file)

current_line = current_line + 1
print_a_line(current_line, current_file)