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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 system_supports_plotting():
 """ Check if x server is running Returns ------- system_supports_plotting : bool True when on Linux and running an xserver. Returns None when on a non-linux platform. """

    try:
        if os.environ['ALLOW_PLOTTING'].lower() == 'true':
            return True
    except KeyError:
        pass
    try:
        p = Popen(["xset", "-q"], stdout=PIPE, stderr=PIPE)
        p.communicate()
        return p.returncode == 0
    except:
        return False