title: Pandas compare multiple columns to a specific column in a dataframe
body: <p>I have a data frame like this:</p>
  
  <pre><code>Product_ID Store_1_qty Store_2_qty Store_3_qty
  A          10          20          10
  B          10          10          10
  C          10          10          20
  </code></pre>
  
  <p>I want to add one more column which says 'true' or 'false' if column Store_2_qty, Store_3_qty are both equal to Store_1_qty. However sometimes extra columns like Store_4_qty, Store_5_qty are added, for which again I need to compare all columns to Store_1_qty</p>
  
  <p>I tried this, but it is returning all False in last column</p>
  
  <pre><code>result['match'] = np.where(result.iloc[:, 1] == result.iloc[:, :1].all(1), 'True', 'False')
  </code></pre>