我已经matplotlib为 Python安装了使用pip它完成的没有错误。然而，当我尝试导入它时出现此错误：
import matplotlib
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/home/rishabh/.local/lib/python2.7/site-packages/matplotlib/__init__.py", line 131, in <module>
from matplotlib.rcsetup import defaultParams, validate_backend, cycler
File "/home/rishabh/.local/lib/python2.7/site-packages/matplotlib/rcsetup.py", line 29, in <module>
from matplotlib.fontconfig_pattern import parse_fontconfig_pattern
File "/home/rishabh/.local/lib/python2.7/site-packages/matplotlib/fontconfig_pattern.py", line 28, in <module>
from backports.functools_lru_cache import lru_cache
ImportError: No module named functools_lru_cache