title: NameError: name 'split' is not defined with Spark
body: <p>I have been working on a big dataset with Spark. Last week when I ran the following lines of code it worked perfectly, now it is throwing an error: NameError: name 'split' is not defined. Can somebody explain why this is not working and what should I do? Name split is not defined... Should I define the method? Is it a dependency that I should import? The documentation doesn't say I ahve to import anything in order to use the split method. The code below.</p>
  
  <pre><code>test_df = spark_df.withColumn(
    "Keywords", 
     split(col("Keywords"), "\\|")
  )
  </code></pre>