Encode decode file as bin

import sys
import random

# Reads file located in the 'file_path' returning its content
def read_file(file_path):
    try:
        file_wrapper = open(file_path, "rb")
        file_content = list(file_wrapper.read())
        file_wrapper.close()

        return file_content
    except IOError as io_error:
        print(f'Cant access file {file_path}', io_error)
        # Returns empty bytearray
        return []

# Writes content to file
def write_file(file_path, content):
    try:
        file_wrapper = open(file_path, 'wb')
        content_as_bytes = bytearray(content)
        file_wrapper.write(content_as_bytes)
        file_wrapper.close()

        return file_path
    except IOError as io_error:
        print(f'Cant access file {file_path}', io_error)
        # Returns empty path
        return ""

# Generates a key with length min(content_length, key_length_limit)
def generate_key(content_length, key_length_limit):
    key_length = min(content_length, key_length_limit)

    generated_key = [random.randint(0, 255) for b in range(key_length)]
    return generated_key

# Applies a key to file content
def encode_decode(file_content, encription_key):
    content_length = len(file_content)
    key_length = len(encription_key)

    encoded_content = []
    encoded_byte_index = 0
    while(encoded_byte_index < content_length):
        encoded_content = [
            byte ^ encription_key[encoded_byte_index % key_length] for byte in file_content
        ]
        encoded_byte_index += 1

    return encoded_content

def main(file_path):
    # Check if file exist
    file_content = read_file(file_path)
    print('File content:', file_content)

    # Generates a random key with the specified max length
    key_max_length = 5
    generated_key = generate_key(len(file_content), key_max_length)
    print('Key content', generated_key)

    # Encodes the content using the specified key
    encoded_content = encode_decode(file_content, generated_key)
    print('Encoded content', encoded_content)

    # Writed the encoded content to a file
    encoded_file_path = write_file(file_path + '_encoded', encoded_content)

    # Reads the file just created back in memory
    file_content = read_file(encoded_file_path)

    # Decodes the file to show the inversion of the encoding
    decoded_content = encode_decode(file_content, generated_key)
    print('Decoded content from file {encoded_file_path}', decoded_content)

if __name__ == "__main__":
    # Parsing arguments
    if(len(sys.argv) != 2):
        error_message = f'Wrong arguments amount, usage: {sys.argv[0]} [filename.ext]'
        print(error_message)

    # Passing argument filepath to main
    main(sys.argv[1])