title: Dashboard in Python widget + interact
body: <p>I have a dataframe with 15 columns and I want to create dropdowns out of those columns populated by dependency on each other. For example, if my first column is 'country' and if I select 'France' then I want all other 10 dropdowns to change their values accordingly to what is in the dataframe for France. </p>
  
  <p>Also, every time I change values in my dropdowns, I want to make different plots acoording to what has been selected in a columns_to_plot dropdown. I have tried everythign I could think of but nothing seems to work and there are no complex examples online where many dropdowns interact. </p>
  
  <p>Example:</p>
  
  <pre><code>dropdown_country = [France, Spain, ....]
  dropdown_year = [1991, 1992, ...]
  dropdown_car = [BMW, Opel, ...]
  dropdown_color = [blue, black, ...]
  </code></pre>
  
  <p>Those are the columns I want to plot against country, year and car columns for example (the rest of columns in  a dataframe are listed in this dropdown, not their values as in dropdowns above):</p>
  
  <pre><code>columns_to_plot_dropdown = [total, sales, ....]
  </code></pre>
  
  <p>So if I select France in a country dropdown I want to see only years in a year dropdown that correspond to France and only cars that correspond to France in year 1992. Color dropdown also needs to be updated only for France in 1992 and selected type of car. </p>
  
  <p>Then if I select sales column in columns_to_plot dropdown I want to plot country, year, car and color columns for sales. </p>
  
  <p>I have tried Python Interact widgets and Dash as well but couldn't make it work. Any help would be much appreciated. </p>