title: labelling variables pd dataframe
body: <p>In df, there are a lot of variables , included of <code>vaccine_preg</code>, <code>only_breastf</code> and so on .</p>
  
  <p>As data dictionary , </p>
  
  <pre><code>vaccine={'1':'Anti Tetanus Toxoid Injection', '2':'Polio Vaccine', '3':'BCG vaccine'}
  yndk={'1':'yes','0':'no','-88':'Prefer not to answer', '-99':"Don't know"}
  
  df=df.vaccine_preg.map(vaccine)
  df=df.only_breastf.map(yndk)
  </code></pre>
  
  <p>I want to do label all variables in data set of this dataframe.
  But , after label to <code>vaccine_preg</code> variable, Could not continue to label next variable : <code>only_breast</code>.</p>
  
  <p>Error is like ;</p>
  
  <blockquote>
    <p>AttributeError: 'Series' object has no attribute 'only_breastf'</p>
  </blockquote>
  
  <p>Help me with this , how to label variables with respective dictionary.</p>