title: How to stack with pandas multiple columns
body: <p>My data is in the following format (so 2 leading columns and then the data I want to stack)</p>
  
  <pre><code>[[TEXT, DATE, H1, H2, H3,...],
   ['ABA',01-01-2018,5,6,7,...],
   [...]]
  </code></pre>
  
  <p>And I need to convert it to (the same 2 leading columns and then the stacked data)</p>
  
  <pre><code>[[TEXT, DATE, PRICE, HOUR],
   ['ABA',01-01-2018,5,H1],
   ['ABA',01-01-2018,6,H2],
   ['ABA',01-01-2018,7,H3]]
  </code></pre>
  
  <p>I have tried stacking it with </p>
  
  <pre><code>data2=data.stack().reset_index().rename(columns={'level_0':'TEXT','level_1':'HOUR', 'level_2:'DATE',0:'PRICE'})
  </code></pre>
  
  <p>but I get as a result</p>
  
  <pre><code>[[TEXT, HOUR, PRICE],
   [0,TEXT,'ABA'],
   [0,DATE,01-01-2018],
   [0,1,5],
   [0,2,6]
   [0,3,7]]
  </code></pre>
  
  <p>I have tried playing with the stack function, but it never gives me the desired result.</p>