title: How do I filter out multiple columns witha certain string in Python
body: <p>I'm new to python and especially to pandas so I don't really know what I'm doing. I have 10 columns with 100000 rows and 4 letter strings. I need to filter out rows which don't contain 'DDD' in all of the columns/rows. </p>
  
  <p>I tried to do it with iloc and loc, but it doesn't work:</p>
  
  <pre class="lang-py prettyprint-override"><code>import pandas as pd
  df = pd.read_csv("data_3.csv", delimiter = '!')
  df.iloc[:,10:20].str.contains('DDD', regex= False, na = False)
  df.head()
  </code></pre>
  
  <p>It returns me an error: 'DataFrame' object has no attribute 'str'</p>