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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 gist_diff():
 """Diff this file with the gist on github"""

    remote_file = wget(RAW_GIST)
    proc = subprocess.Popen(('diff - %s'%MY_PATH).split(),
                            stdin=subprocess.PIPE,
                            stdout=subprocess.PIPE)
    stdout, stderr = proc.communicate(remote_file)
    return stdout