ml" class="external-link">install_github</a></span><span class="op">(</span><span class="st">"mountainmath/tongfen"</span><span class="op">)</span></span>
<span><span class="kw"><a href="https://rdrr.io/r/base/library.html" class="external-link">library</a></span><span class="op">(</span><span class="va"><a href="https://github.com/mountainMath/tongfen" class="external-link">tongfen</a></span><span class="op">)</span></span></code></pre>
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