I/O 操作を使用して Python スクリプトから出力をキャプチャする方法

<code class="python"># writer.py
import sys

def write():
    sys.stdout.write("foobar")

# mymodule.py
from writer import write

out = write()
print(out.upper())</code>

<code class="python">import sys
from cStringIO import StringIO

# setup the environment
backup = sys.stdout

# ####
sys.stdout = StringIO()     # capture output
write()
out = sys.stdout.getvalue() # release output
# ####

sys.stdout.close()  # close the stream 
sys.stdout = backup # restore original stdout

print(out.upper())   # post processing</code>

<code class="python">from contextlib import redirect_stdout
import io

f = io.StringIO()
with redirect_stdout(f):
    help(pow)
s = f.getvalue()</code>