title: Create a dictionary where the keys are values of dictionaries inside lists in a dictionary and the values are the number of times they appear
body: <p>I have this dictionary of lists of dictionaries (I cannot change the structure for the work):</p>
  <pre><code>dict_countries = {'gb': [{'datetime': '1955-10-10 17:00:00', 'city': 'chester'}, 
                           {'datetime': '1974-10-10 23:00:00', 'city': 'chester'}], 
                    'us': [{'datetime': '1955-10-10 17:00:00', 'city': 'hudson'}]
                   }
  </code></pre>
  <p>And the function:</p>
  <pre><code>def Seen_in_the_city(dict_countries:dict,)-&gt; dict:
      city_dict = {}
      for each_country in dict_countries.values():   
          for each_sight in each_country: 
              citi = each_sight[&quot;city&quot;]
              if citi in city_dict.keys():
                  city_dict[each_sight[&quot;city&quot;]] =+1 
              else:
                  city_dict[citi] =+1        
      return city_dict
  </code></pre>
  <p>I get:</p>
  <pre><code>{'chester': 1,'hudson': 1}
  </code></pre>
  <p>instead of</p>
  <pre><code>{'chester': 2,'hudson': 1}
  </code></pre>