src/transformers/models/lxmert/modeling_lxmert.py/LxmertXLayer/self_att
class LxmertXLayer:    def self_att(self, lang_input, lang_attention_mask, visual_input, visual_attention_mask):
        # Self Attention
        lang_att_output = self.lang_self_att(lang_input, lang_attention_mask, output_attentions=False)
        visual_att_output = self.visn_self_att(visual_input, visual_attention_mask, output_attentions=False)
        return lang_att_output[0], visual_att_output[0]