title: Filter df when values matches part of a string in pyspark
body: <p>I have a large <code>pyspark.sql.dataframe.DataFrame</code> and I want to keep (so <code>filter</code>) all rows where the URL saved in the <code>location</code> column contains a pre-determined string, e.g. 'google.com'.</p>
  
  <p>I have tried:</p>
  
  <pre><code>import pyspark.sql.functions as sf
  df.filter(sf.col('location').contains('google.com')).show(5)
  </code></pre>
  
  <p>but this throws a </p>
  
  <pre><code>TypeError: _TypeError: 'Column' object is not callable'
  </code></pre>
  
  <p>How do I go around and filter my df properly? Many thanks in advance! </p>