title: Getting "ValueError: cannot reindex from a duplicate axis: " as I want to multiply specific columns bases on value of another column
body: <p>I want to multiply certain columns based on value of another column.</p>
  <pre><code>   merged.loc[merged.check.str.contains('1'), 'price'] = merged['price']*100000.0
     merged.head()
  </code></pre>
  <hr />
  <p>But I am getting this error.</p>
  <pre><code>ValueError: cannot reindex from a duplicate axis
  </code></pre>