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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 copy_artifacts(app):
 """Copies artifacts needed for website presentation"""

    dest_path = app.builder.outdir + '/error'
    source_path = app.builder.srcdir + '/build_version_doc/artifacts'
    _run_cmd('cd ' + app.builder.srcdir)
    _run_cmd('rm -rf ' + dest_path)
    _run_cmd('mkdir -p ' + dest_path)
    _run_cmd('cp ' + source_path + '/404.html ' + dest_path)
    _run_cmd('cp ' + source_path + '/api.html ' + dest_path)
    dest_path = app.builder.outdir + '/_static'
    _run_cmd('rm -rf ' + dest_path)
    _run_cmd('mkdir -p ' + dest_path)
    _run_cmd('cp ' + app.builder.srcdir + '/_static/mxnet.css ' + dest_path)