pandas split one column into multiple KeyError
<pre><code>df = age;"job";"marital";"education";"default";"housing";"loan";"contact";"month";"day_of_week";"duration";"campaign";"pdays";"previous";"poutcome";"emp.var.rate";"cons.price.idx";"cons.conf.idx";"euribor3m";"nr.employed";"y"
0  30;"blue-collar";"married";"basic.9y";"no";"ye...                                                                                                                                                                          
1  39;"services";"single";"high.school";"no";"no"...                                                                                                                                                                          
2  25;"services";"married";"high.school";"no";"ye...                                                                                                                                                                          
3  38;"services";"married";"basic.9y";"no";"unkno...                                                                                                                                                                          
4  47;"admin.";"married";"university.degree";"no"...                                                                                                                                                                          
5  32;"services";"single";"university.degree";"no...                                                                                                                                                                          
6  32;"admin.";"single";"university.degree";"no";...                                                                                                                                                                          
7  41;"entrepreneur";"married";"university.degree...                                                                                                                                                                          
8  31;"services";"divorced";"professional.course"...                                                                                                                                                                          
9  35;"blue-collar";"married";"basic.9y";"unknown... 
</code></pre>

<p>There are 21 attributes, I want to split one column into 21 column.</p>

<p><code>df['1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21'].apply(lambda x: pd.Series(x.split(';')))</code></p>

<p>and it returns: </p>

<blockquote>
  <p>KeyError: '1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20'</p>
</blockquote>

<p>What's the problem?</p>