title: How do keep only unique words within each string in a vector
body: <p>I have data that looks like this:</p>
  
  <pre><code>vector = c("hello I like to code hello","Coding is fun", "fun fun fun")
  </code></pre>
  
  <p>I want to remove duplicate words (space delimited) i.e. the output should look like</p>
  
  <p>vector_cleaned</p>
  
  <pre><code>[1] "hello I like to code"
  [2] "coding is fun"
  [3] "fun"
  </code></pre>