lesson_3.py

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# DAY 3
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# FILE HANDLING - READING FILES AND WRITING FILES

from sys import argv

script, filename = argv

print(f"We're going to delete {filename}.")
print("To cancel, hit CTRL-C (^C).")
print("To proceed, hit RETURN.")

input('?')

# prints an indication, then opens the file
# w means opens the file as a writable file
print("Opening {filename}...")
target = open(filename, 'w')

# truncate, means deleting the content of the file
print("Deleting the content of {}...".format(filename))
target.truncate()

# asking for input then writes it in the file
print("Gimme three lines.")
line1 = input("line 1: ")
line2 = input("line 2: ")
line3 = input("line 3: ")

target.write(line1)
target.write("\n")
target.write(line2)
target.write("\n")
target.write(line3)
target.write("\n")
# or a prettier approach
target.write(f"{line1}\n{line2}\n{line3}")

# then closes the file
print(f"Closing the {filename}...")
target.close()

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from sys import argv
from os.path import exists


script, from_file, to_file = argv

print(f"Will copy from {from_file} to {to_file}.")

# opens the file that is passed as an argument
in_file = open(from_file)
indata = in_file.read()

# prints if the file exists
print(f"Does the file exist? {exists(to_file)}")
print("Ready? Hit enter to continue, CTRL-C to abort.")
input()

# opens the file that will be written upon
# this process overwrites the file
out_file = open(to_file, 'w')
out_file.write(indata)

print("DONE!")

# closes both files
out_file.close()
in_file.close()


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