#NEWLINE# def fdiff( self , argindex = 1 ) : #NEWLINE# #INDENT# if ( argindex == 1 ) : #NEWLINE# #INDENT# z = self . args [ 0 ] #NEWLINE# return ( ( S . One / self ) - _eis ( z ) ) #NEWLINE# #UNINDENT# else : #NEWLINE# #INDENT# raise ArgumentIndexError ( self , argindex )