title: check if dictionary key has empty value
body: <p>I have the following dictionary</p>
  
  <pre><code>dict1 ={"city":"","name":"yass","region":"","zipcode":"",
         "phone":"","address":"","tehsil":"", "planet":"mars"}
  </code></pre>
  
  <p>I am trying to create a new dictionary that will be based on dict1 but,</p>
  
  <ol>
  <li>it will not contain keys with empty strings.</li>
  <li>it will not contain those keys that I dont want to include.</li>
  </ol>
  
  <p>i have been able to fulfill the requirement 2 but getting problem with requirement 1. Here is what my code looks like.</p>
  
  <pre><code>dict1 ={"city":"","name":"yass","region":"","zipcode":"",
     "phone":"","address":"","tehsil":"", "planet":"mars"}
  
  blacklist = set(("planet","tehsil"))    
  new = {k:dict1[k] for k in dict1 if k not in blacklist} 
  </code></pre>
  
  <p>this gives me the dictionary without the keys: "tehsil", "planet"
  I have also tried the following but it didnt worked.</p>
  
  <pre><code>new = {k:dict1[k] for k in dict1 if k not in blacklist and dict1[k] is not None}
  </code></pre>
  
  <p>the resulting dict should look like the one below:</p>
  
  <pre><code>new = {"name":"yass"}
  </code></pre>