Context managers: with (file) experiments

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examples/advanced/with_file_write.py

with open('out.txt', 'w') as h:
    h.write("hello\n")

h = open('out.txt')
print(h.read())

f = open('out.txt', 'w')
f.write("hello\n")
f.close()

# for line in open("myfile.txt"):
#    print line,
# the file is closed only when script ends