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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 latexpdf():
 """make LaTeX files and run them through pdflatex"""

    rc = latex()
    print('Running LaTeX files through pdflatex...')
    builddir = os.path.join(BUILDDIR, 'latex')
    subprocess.call(['make', '-C', builddir, 'all-pdf'])
    print('pdflatex finished; the PDF files are in {}.'.format(builddir))