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ax1.legend("HHZ 1",loc="upper right")
ax2.legend("HHN",loc="upper right")
ax3.legend("HHE",loc="upper right")
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handles, labels = ax.get_legend_handles_labels()
fig.legend(handles, labels, loc='upper center')
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plt.legend(bbox_to_anchor = (1,0.5), loc = 'center right', fontsize = 15, bbox_transform=plt.gcf().transFigure)
plt.subplots_adjust(left=0.0, bottom=0.1, right=0.5)