The parity of part objects

Does "the parity of part objects" in the following context mean "parts being only parts and none of them being whole" or "parts being equivalent to each other and none of them being of higher value than the others"?

Context:

For Nixon, the most emblematic image of this creative aggression is the 1982 photograph by Robert Mapplethorpe of Bourgeois holding her 1968 sculpture La Fillette. She says,

In Mapplethorpe’s photograph, Bourgeois made herself the very image of the bad enough mother: the mother who grins at the patriarchal overvaluation of the phallus, who parodies the metonymy of infant and penis, and in whose hands the phallus becomes penis or in other words slips from its status as prevailed signifier to become one more object of aggression and desire.

Nixon is here alluding to the parity of part objects in the Kleinian universe of phantasy: penis, breasts, milk – all are objects of desire and attack. Although Klein’s ‘emphasis on the importance of the mother in infantile phantasy [...] should not be mistaken as a reconceptualisation of sexual difference’, Nixon’s reading of artworks through the lens of Kleinian phantasy does open up a more fluid play of difference reminiscent of the mobility of the fetish that I explored in the Chapter 3, whereby objects are exchanged in a relay of equivalences, the penis becoming a part object alongside other objects rather than a privileged signifier of the phallus.