IO with basic file.py

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

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# this %% magic is only available in jupyter notebook to write text file


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get_ipython().run_cell_magic('writefile', 'myfile.txt', 'hello this is a text file\nmy name is uzair')


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# opening file that created above
myfile = open('myfile.txt')


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myfile.read()


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pwd


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# after first time .read function returns empty string because when first time reads than cursor moves to end that is why
myfile.read()


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#  solution -- seek(0) return the cursor to 0 
myfile.seek(0)
myfile.read()


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myfile.seek(0)
myfile.readlines()


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# open file with file lcoation 
# full file path = 'C:\\User\\ ..' in windows
# full file path = 'User/yourname/ ..' in macOs

# myfile = open('full file path')


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# we should close after reada the file because its opened because it will return error 'this file is using somewhere else'
myfile.close()


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# to avoid previous error in shown in comment best practice to read the file is use special 'with statement'

with open('myfile.txt') as my_new_file:
    contents = my_new_file.read()


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contents


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# we also use mode read or write 
with open('myfile.txt',mode='r') as my_new_file:
    contents = my_new_file.read()


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contents


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# r = read only
# w = write only
# a = append only
# r+ = is reading and writing
# w+ = is writng and reading overwrite existing file or creates a new file

with open('myfile.txt',mode='w') as my_new_file:
    my_new_file.write('writng the file')


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with open('myfile.txt',mode='r') as my_new_file:
    print(my_new_file.read())


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