Original: In 1836, at a party hosted by Countess Marie d'Agoult, mistress of friend and fellow composer Franz Liszt, Chopin met French author and feminist Amandine Aurore Lucille Dupin, the Baroness Dudevant, better known by her pseudonym, George Sand.
Simplified: At about this time Chopin met the woman writer Amandine-Aurore-Lucile Dupin, the Baroness Dudevant, better known as George Sand.