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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def urlretrieve(url, dest, write_mode="w"):
 """save a file to disk from a given url"""

    response = urllib2.urlopen(url)
    mkdir_recursive(os.path.dirname(dest))
    with open(dest, write_mode) as f:
        f.write(response.read())
        f.close()