old_contents: from city_visitor import CityVisitor
  import matplotlib.pyplot as plt
  
  
  class StreetPlotGenerator(CityVisitor):
  
      def write_to(self, destination_file):
          plt.figure(figsize=(20, 20), dpi=100)
          self.run()
          plt.savefig(destination_file, dpi=100)
  
      def draw_lane(self, lane):
          x = []
          y = []
          for point in lane.geometry():
              x.append(point.x)
              y.append(point.y)
          return plt.plot(x, y)
  
      def start_street(self, street):
          for lane in street.get_lanes():
              line = self.draw_lane(lane)
              plt.setp(line, linewidth=1)
  
      def start_trunk(self, trunk):
          for lane in trunk.get_lanes():
              line = self.draw_lane(lane)
              plt.setp(line, linewidth=2)
  
new_contents: from city_visitor import CityVisitor
  import matplotlib.pyplot as plt
  
  
  class StreetPlotGenerator(CityVisitor):
  
      def write_to(self, destination_file):
          plt.figure(figsize=(20, 20), dpi=150)
          self.run()
          plt.savefig(destination_file, dpi=150)
  
      def draw_lane(self, lane):
          x = []
          y = []
          for point in lane.geometry():
              x.append(point.x)
              y.append(point.y)
          return plt.plot(x, y)
  
      def start_street(self, street):
          for lane in street.get_lanes():
              line = self.draw_lane(lane)
              plt.setp(line, linewidth=1)
  
      def start_trunk(self, trunk):
          for lane in trunk.get_lanes():
              line = self.draw_lane(lane)
              plt.setp(line, linewidth=1)
  
subject: Tweak street plot generator