matplotlib error

[miguelfs]

Hi, folks.
It may be something in my machine. I'm not sure.
I ran pip install . like mentioned in the README.md.

(base) amplitude-modulation-analysis-module miguel$ python3 example_03.py 
3.3005948066711426 seconds
0.7930810451507568 seconds
Traceback (most recent call last):
  File "example_03.py", line 145, in <module>
    plt.hold
AttributeError: module 'matplotlib.pyplot' has no attribute 'hold'

(base) MacBook-Air-de-Miguel:amplitude-modulation-analysis-module miguel$ python3
Python 3.7.7 (default, Mar 26 2020, 10:32:53) 
[Clang 4.0.1 (tags/RELEASE_401/final)] :: Anaconda, Inc. on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import matplotlib
>>> print('matplotlib: {}'.format(matplotlib.__version__))
matplotlib: 3.2.2
>>>