#!/usr/bin/env python
# coding: utf-8

# # Chapter 21 File Input and Output
# 
# <img align="left" src="https://i.imgur.com/lnc0qMV.png" />

# In[1]:


# 01 백문이 불여일견

my_list = [i**2 for i in range(1,11)]
# Generates a list of squares of the numbers 1 - 10

f = open("output.txt", "w")

for item in my_list:
    f.write(str(item) + "\n")

f.close()


#
# check output.txt


# In[2]:


# 02 open() 함수

my_file = open("output.txt", "r+")


# In[3]:


# 03 쓰기(Writing)

my_list = [i**2 for i in range(1,11)]

my_file = open("output.txt", "r+")

# Add your code below!
for e in my_list:
    my_file.write(str(e) + "\n")

my_file.close()


# In[4]:


# 04 읽기(Reading)

my_file = open("output.txt", "r")

print (my_file.read())

my_file.close()


# In[5]:


# 05 한 줄씩 읽어나가기

my_file = open("output.txt", "r")

print (my_file.readline())
print (my_file.readline())
print (my_file.readline())

my_file.close()


# In[6]:


# 06 데이터 버퍼링(Data Buffering)

# Open the file for reading
read_file = open("output.txt", "r")

# Use a second file handler to open the file for writing
write_file = open("text.txt", "w")
# Write to the file
write_file.write("Not closing files is VERY BAD.")

write_file.close()

# Try to read from the file
print (read_file.read())
read_file.close()


# In[7]:


# 07 'with'와 'as' 키워드

with open("text.txt", "w") as textfile:
    textfile.write("Success!")


# In[8]:


# 08 혼자 힘으로 해보세요

with open("text.txt", "w") as my_file:
    my_file.write("HOHOHOHOHO~~~~!!")
    


# In[9]:


# 09 제대로 닫혔나요?

with open("text.txt", "w") as my_file:
    my_file.write("HOHOHOHOHO~~~~!!")

print (my_file.closed)

if my_file.closed == False:
    my_file.close()

print (my_file.closed)