annotation_col <- data.frame(condition = md$condition[mm],
  row.names = colnames(expr_median_sample))

annotation_colors <- list(condition = color_conditions)

color <- colorRampPalette(brewer.pal(n = 9, name = "YlGnBu"))(100)

pheatmap(expr_median_sample, color = color, display_numbers = TRUE, 
  number_color = "black", fontsize_number = 5, annotation_col = annotation_col, 
  annotation_colors = annotation_colors, clustering_method = "average")