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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 runDia(diagram):
 """Generate the diagrams using Dia."""

    ifname = '{}.dia'.format(diagram)
    ofname = '{}.png'.format(diagram)
    cmd = 'dia -t png-libart -e {} {}'.format(ofname, ifname)
    print('  {}'.format(cmd))
    subprocess.call(cmd, shell=True)
    return True