legend(loc # Location code string, or tuple (see below).
# 圖例所有figure位置。 labels # 標簽名稱。
prop # the font property.
# 字體參數
fontsize # the font size (used only if prop is not specified).
# 字號大小。
markerscale # the relative size of legend markers vs.
# original 圖例標記與原始標記的相對大小
markerfirst # If True (default), marker is to left of the label.
# 如果為True，則圖例標記位於圖例標簽的左側
numpoints # the number of points in the legend for line.
# 為線條圖圖例條目創建的標記點數
scatterpoints # the number of points in the legend for scatter plot.
# 為散點圖圖例條目創建的標記點數
scatteryoffsets # a list of yoffsets for scatter symbols in legend.
# 為散點圖圖例條目創建的標記的垂直偏移量
frameon # If True, draw the legend on a patch (frame).
# 控制是否應在圖例周圍繪制框架
fancybox # If True, draw the frame with a round fancybox.
# 控制是否應在構成圖例背景的FancyBboxPatch周圍啟用圓邊
shadow # If True, draw a shadow behind legend.
# 控制是否在圖例后面畫一個陰影
framealpha # Transparency of the frame.
# 控制圖例框架的 Alpha 透明度
edgecolor # Frame edgecolor.
facecolor # Frame facecolor.
ncol # number of columns.
# 設置圖例分為n列展示
borderpad # the fractional whitespace inside the legend border.
# 圖例邊框的內邊距
labelspacing # the vertical space between the legend entries.
# 圖例條目之間的垂直間距
handlelength # the length of the legend handles.
# 圖例句柄的長度
handleheight # the height of the legend handles.
# 圖例句柄的高度
handletextpad # the pad between the legend handle and text.
# 圖例句柄和文本之間的間距
borderaxespad # the pad between the axes and legend border.
# 軸與圖例邊框之間的距離
columnspacing # the spacing between columns.
# 列間距
title # the legend title.
# 圖例標題
bbox_to_anchor # the bbox that the legend will be anchored.
# 指定圖例在軸的位置
bbox_transform) # the transform for the bbox.
# transAxes if None.
matplotlib 的 legend 官網：https://matplotlib.org/users/legend_guide.html