title: F String Invalid Syntax in Python 3.5
body: <p>I know that <code>F Strings</code> were introduce in <code>Python 3.6</code>. For that i was getting error - <code>Invalid Syntax</code></p>
  
  <pre><code>DATA_FILENAME = 'data.json'
  def load_data(apps, schema_editor):
      Shop = apps.get_model('shops', 'Shop')
      jsonfile = Path(__file__).parents[2] / DATA_FILENAME
  
      with open(str(jsonfile)) as datafile:
          objects = json.load(datafile)
          for obj in objects['elements']:
              try:
                  objType = obj['type']
                  if objType == 'node':
                      tags = obj['tags']
                      name = tags.get('name','no-name')
                      longitude = obj.get('lon', 0)
                      latitude = obj.get('lat', 0)
                      location = fromstr(F'POINT({longitude} {latitude})', srid=4326)
                      Shop(name=name, location = location).save()
              except KeyError:
                  pass    
  </code></pre>
  
  <p>Error - </p>
  
  <pre><code>location = (F'POINT({longitude} {latitude})', srid=4326)
                                             ^
  SyntaxError: invalid syntax
  </code></pre>
  
  <p>So i used - </p>
  
  <pre><code>fromstr('POINT({} {})'.format(longitude, latitude), srid=4326)
  </code></pre>
  
  <p>The Error was removed and it worked for me. Then i found this library <a href="https://github.com/asottile/future-fstrings" rel="noreferrer">future-fstrings</a>. Should i use it. Which will remove the above <code>Invalid Error</code></p>