title: Get the last column of a pd.dataFrame and add it to another pd.dataFrame
body: <p>I have an Excel file that looks like this:</p>
  
  <pre><code>CompanyName    High Priority     QualityIssue
  Customer1         Yes             User
  Customer1         Yes             User
  Customer2         No              User
  Customer3         No              Equipment
  Customer1         No              Neither
  Customer3         No              User
  Customer3         Yes             User
  Customer3         Yes             Equipment
  Customer4         No              User
  </code></pre>
  
  <p>I want to count how many time each instance in <code>CompanyName</code> appears per every type of <code>QualityIssue</code> and sort by the number of appearance descend.</p>
  
  <p>For example, by using this code:</p>
  
  <pre><code>df.groupby(["CompanyName ", "QualityIssue"]).size().to_frame('Count')
  </code></pre>
  
  <p>I get:</p>
  
  <pre><code>Out:
  
  CompanyName       QualityIssue    Count
  Customer2         User            1
  Customer1         Neither         1
  Customer4         User            1
  Customer1         User            2
  Customer3         Equipment       2
  Customer3         User            2
  </code></pre>
  
  <p>And then let's say that I have another copy of the above in memory.</p>
  
  <p>What I want is to add the last column of the second query to the end of the first one (In reality it won't be a copy of it, it's just an example):</p>
  
  <pre><code>CompanyName       QualityIssue    Count1    Count2
  Customer2         User            1        1
  Customer1         Neither         1        1
  Customer4         User            1        1
  Customer1         User            2        2
  Customer3         Equipment       2        2
  Customer3         User            2        2      
  </code></pre>
  
  <p>The problem here is that if I do </p>
  
  <pre><code>df['Count'] 
  </code></pre>
  
  <p>it will not print only that column, it will print everything, just like doing </p>
  
  <pre><code>print df  
  </code></pre>
  
  <p>So I cannot find a way to get only the last column of the dataFrame to add it to another one.</p>