how to merge two dataframes and sum the values of columns : <p>I have two dataframes</p>

<pre><code>df1
Name class value
Sri   1     5
Ram   2     8
viv   3     4

df2
Name class value
Sri   1     5
viv   4     4
</code></pre>

<p>My desired output is,</p>

<pre><code>df,

Name class value
Sri   2     10
Ram   2     8
viv   7     8
</code></pre>

<p>Please help, thanks in advance!</p>
