code: def ln(self, h=''):
          "Line Feed; default value is last cell height"
          self.x=self.l_margin
          if(isinstance(h, basestring)):
              self.y+=self.lasth
          else:
              self.y+=f ln(self, h=''):
          "Line Feed; default value is last cell height"
          self.x=self.l_margin
          if(isinstance(h, basestring)):
              self.y+=self.lasth
          else:
              self.y+=h
docs: Line Feed; default value is last cell height