<span class="sd">  Returns</span>
<span class="sd">  -------</span>
<span class="sd">  A list of (`type`, `num_of_type`) tuples for each unique data type.</span>

<span class="sd">  &quot;&quot;&quot;</span>
  <span class="n">g</span> <span class="o">=</span> <span class="n">df</span><span class="o">.</span><span class="n">columns</span><span class="o">.</span><span class="n">to_series</span><span class="p">()</span><span class="o">.</span><span class="n">groupby</span><span class="p">(</span><span class="n