code: def add(self, name, value, unit=None):
          
          # check if unit provided
          if unit is not None:
              add_unit = True
              unit = str(unit)
          else:
              add_unit = False
  
          # convert value to string
          value = str(value)
  
          # write to file
          f = open(self.file_dir, 'a')
          if add_unit:
              f.write("\\pgfkeys{dynamicnumber/%s/%s = \unit{%s}{%s}}\n" % (self.name, name, value, unit))
          else:
              f.write("\\pgfkeys{dynamicnumber/%s/%s = %s}\n" % (self.name, name, value))
          f.close()
docs: Add symbolic link to Dynamic Number list.
  
          name  -- name of the symbolic link
          value -- value of the link (if not a string, conversion is done with str())
          unit  -- if value is a numerical value, a unit can be added to invoke the \unit{}{} LaTeX command