python 3.x - How can I open a file in write, close it, and then reopen it in read? -


i writing code school , having problems re-opening file after have closed it.

test=open('test.txt','w') ....... test.close  retest=open('test.txt','r')

this exact error message getting:

typeerror: invalid file: <_io.textiowrapper name='test.txt'           mode='w' encoding='cp1252'>

you need close file test.close(). without (), test.close not being called, referenced, , file still open when try reopen it.

better yet, can use context managers, , file closed automatically:

with open('test.txt', 'w') test:     ... open('test.txt', 'r') retest:     ...

or better still (depending on use case), use r+ mode open file reading and writing @ same time:

with open('test.txt', 'r+') test:     # read , write file necessary

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