title: Pandas Error for creating an emptydataframe
body: <p>I tried making a dummy dataframe,</p>
  <p><code>column_names = [&quot;a&quot;, &quot;b&quot;, &quot;c&quot;]</code></p>
  <p><code>df = pd.DataFrame(columns = column_names)</code></p>
  <p>I am getting the following error, this was not happening before, am I missing something. This is only happening on the creation of an empty dataframe, is this a recently introduced bug.</p>
  <pre><code>  File &quot;&lt;stdin&gt;&quot;, line 1, in &lt;module&gt;
    File &quot;/usr/local/lib/python3.7/site-packages/pandas/core/frame.py&quot;, line 411, in __init__
      mgr = init_dict(data, index, columns, dtype=dtype)
    File &quot;/usr/local/lib/python3.7/site-packages/pandas/core/internals/construction.py&quot;, line 242, in init_dict
      val = construct_1d_arraylike_from_scalar(np.nan, len(index), nan_dtype)
    File &quot;/usr/local/lib/python3.7/site-packages/pandas/core/dtypes/cast.py&quot;, line 1221, in construct_1d_arraylike_from_scalar
      dtype = dtype.dtype
  AttributeError: type object 'object' has no attribute 'dtype'
  
  </code></pre>
  <p><a href="https://i.stack.imgur.com/dWaO0.png" rel="noreferrer"><img src="https://i.stack.imgur.com/dWaO0.png" alt="Sample code" /></a></p>