ค้นหานามสกุลของบุคคลที่ติดต่อกับบุคคลในองค์กร
Find the last name of the individuals that have been contact individuals of an organization.
df_individuals = pd.DataFrame(columns=['individual_last_name', 'individual_id']); df_organization_contact_individuals = pd.DataFrame(columns=['individual_id'])
df_individuals[df_individuals['individual_id'].isin(df_organization_contact_individuals['individual_id'])]['individual_last_name'].unique()