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)

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