title: Convert One Column in Python Dataframe to List
body: <p>I have a pandas dataframe consisting of only one column of data.  I want to convert the column of data into a list.  The column has float datatype.    </p>
  
  <p>For example: </p>
  
  <pre><code>ColA
  341321432
  132184900
  173840143
  1432473928
  </code></pre>
  
  <p>Desired: 
  341321432, 132184900, 173840143, 1432473928 </p>
  
  <p>Below is my Python code: </p>
  
  <pre><code>df_gearME = pd.read_excel('Gear M&amp;Es.xlsx')
  df_gearME['ColA'].to_list()
  </code></pre>
  
  <p>But the error I get is as follows: </p>
  
  <pre><code>AttributeError: 'Series' object has no attribute 'to_list'
  </code></pre>