title: Pandas DataFrame 'Date' Column has no header / dtypes / not listed in df.columns
body: <p>I'm importing data from <code>nasdaqdatalink</code> api</p>
  <p>Two questions from this:</p>
  <ul>
  <li>(1) How is this already a Pandas DataFrame without me needing to type <code>df = pd.DataFrame</code> ?</li>
  <li>(2) The 'Date' column, doesn't appear to be a DataFrame column? if I try <code>df.columns</code> it doesn't show up in the index and obviously has no header. So I am confused on what's happening here.</li>
  </ul>
  <p>Essentially, I wanted to select data from this DataFrame between two dates, but the only way I really know how to do that is by selecting the column name first. However, I'm missing something here. I tried to rename the column in position [0] but that just created a new column named 'Date' with NaN values.</p>
  <p>What am I not understanding? (I've only just begun learning Python, Pandas etc. ~1 month ago ! so this is about as far as I could go on my own without more help)</p>
  <p><a href="https://i.stack.imgur.com/7kdCT.jpg" rel="nofollow noreferrer">screenshot</a></p>