code: def get_cfcompliant_units(units, prefix='', suffix=''):
      
      compliant_units = units
  
      for gcunits, udunits in UNITS_MAP_CTM2CF:
          compliant_units = str.replace(compliant_units, gcunits, udunits)
  
      return prefix + compliant_units + suffix
docs: Get equivalent units that are compatible with the udunits2 library
      (thus CF-compliant).
  
      Parameters
      ----------
      units : string
          A string representation of the units.
      prefix : string
          Will be added at the beginning of the returned string
          (must be a valid udunits2 expression).
      suffix : string
          Will be added at the end of the returned string
          (must be a valid udunits2 expression).
  
      Returns
      -------
      A string representation of the conforming units.
  
      References
      ----------
      The udunits2 package : http://www.unidata.ucar.edu/software/udunits/
  
      Notes
      -----
      This function only relies on the table stored in :attr:`UNITS_MAP_CTM2CF`.
      Therefore, the units string returned by this function is not certified to
      be compatible with udunits2.
  
      Examples
      --------
      >>> get_cfcompliant_units('molec/cm2')
      'count/cm2'
      >>> get_cfcompliant_units('v/v')
      '1'
      >>> get_cfcompliant_units('ppbC', prefix='3')
      '3ppb