code: def from_string(cls, string):
      
      # Note: There is some ambiguity as to whether the string passed is intended
      # to become a unit looked up by name or suffix, or a Dimension descriptor.
      if string in units.UNITS_BY_ALL:
        return cls(description=string, unit=units.Unit(string))
      else:
        return cls(description=string)
docs: Convert a string into a Dimension