title: Cannot find index of corresponding date in pandas DataFrame
body: <p>I have the following DataFrame with a <code>Date</code> column,</p>
  <pre><code>0      2021-12-13
  1      2021-12-10
  2      2021-12-09
  3      2021-12-08
  4      2021-12-07
            ...    
  7990   1990-01-08
  7991   1990-01-05
  7992   1990-01-04
  7993   1990-01-03
  7994   1990-01-02
  </code></pre>
  <p>I am trying to find the index for a specific date in this DataFrame using the following code,</p>
  <pre><code># import raw data into DataFrame
  df = pd.DataFrame.from_records(data['dataset']['data'])
  df.columns = data['dataset']['column_names']    
  df['Date'] = pd.to_datetime(df['Date'])
  # sample date to search for
  sample_date = dt.date(2021,12,13)
  print(sample_date)
  # return index of sample date
  date_index = df.index[df['Date'] == sample_date].tolist()
  print(date_index)
  </code></pre>
  <p>The output of the program is,</p>
  <pre><code>2021-12-13
  []
  </code></pre>
  <p>I can't understand why. I have cast the <code>Date</code> column in the DataFrame to a <code>DateTime</code> and I'm doing a like-for-like comparison.</p>