title: matplotlib 3.0.0, cannot import name 'get_backend' from 'matplotlib'
body: <p>Using Windows 10, anaconda as a package manager. I have a base environment running python 3.7 where matplotlib works fine. When I create a new environment and install both keras and matplotlib, I start to run into problems:</p>
  
  <pre><code>&gt;&gt;&gt; import matplotlib.pyplot as plt
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
    File "C:\...\Anaconda3\envs\keras_env\lib\site-packages\matplotlib\__init__.py", line 1111, in &lt;module&gt;
      rcParamsOrig = RcParams(rcParams.copy())
    File "C:\...\Anaconda3\envs\keras_env\lib\site-packages\matplotlib\__init__.py", line 891, in __getitem__
      from matplotlib import pyplot as plt
    File "C:\...\Anaconda3\envs\keras_env\lib\site-packages\matplotlib\pyplot.py", line 32, in &lt;module&gt;
      import matplotlib.colorbar
    File "C:\...\Anaconda3\envs\keras_env\lib\site-packages\matplotlib\colorbar.py", line 40, in &lt;module&gt;
      import matplotlib._constrained_layout as constrained_layout
    File "C:\...\Anaconda3\envs\keras_env\lib\site-packages\matplotlib\_constrained_layout.py", line 52, in &lt;module&gt;
      from matplotlib.legend import Legend
    File "C:\...\Anaconda3\envs\keras_env\lib\site-packages\matplotlib\legend.py", line 43, in &lt;module&gt;
      from matplotlib.offsetbox import HPacker, VPacker, TextArea, DrawingArea
    File "C:\...\Anaconda3\envs\keras_env\lib\site-packages\matplotlib\offsetbox.py", line 33, in &lt;module&gt;
      from matplotlib.image import BboxImage
    File "C:\...\Anaconda3\envs\keras_env\lib\site-packages\matplotlib\image.py", line 19, in &lt;module&gt;
      from matplotlib.backend_bases import FigureCanvasBase
    File "C:\...\Anaconda3\envs\keras_env\lib\site-packages\matplotlib\backend_bases.py", line 46, in &lt;module&gt;
      from matplotlib import (
  ImportError: cannot import name 'get_backend'
  </code></pre>
  
  <p>Any suggestions? This is a fresh installation of conda. All I've done to get here is run <code>conda create --name keras_env keras matplotlib</code>, enter the environment, and try to import matplotlib. These are the packages conda installs:</p>
  
  <pre><code>## Package Plan ##
  
  environment location: C:\...\Anaconda3\envs\keras_env
  
  added / updated specs:
  - keras
  - matplotlib
  
  
  The following NEW packages will be INSTALLED:
  
  _tflow_select:       2.2.0-eigen
  absl-py:             0.5.0-py36_0
  astor:               0.7.1-py36_0
  blas:                1.0-mkl
  ca-certificates:     2018.03.07-0
  certifi:             2018.10.15-py36_0
  cycler:              0.10.0-py36h009560c_0
  freetype:            2.9.1-ha9979f8_1
  gast:                0.2.0-py36_0
  grpcio:              1.12.1-py36h1a1b453_0
  h5py:                2.8.0-py36h3bdd7fb_2
  hdf5:                1.10.2-hac2f561_1
  icc_rt:              2017.0.4-h97af966_0
  icu:                 58.2-ha66f8fd_1
  intel-openmp:        2019.0-118
  jpeg:                9b-hb83a4c4_2
  keras:               2.2.4-0
  keras-applications:  1.0.6-py36_0
  keras-base:          2.2.4-py36_0
  keras-preprocessing: 1.0.5-py36_0
  kiwisolver:          1.0.1-py36h6538335_0
  libpng:              1.6.35-h2a8f88b_0
  libprotobuf:         3.6.0-h1a1b453_0
  markdown:            3.0.1-py36_0
  matplotlib:          3.0.0-py36hd159220_0
  mkl:                 2019.0-118
  mkl_fft:             1.0.6-py36hdbbee80_0
  mkl_random:          1.0.1-py36h77b88f5_1
  numpy:               1.15.3-py36ha559c80_0
  numpy-base:          1.15.3-py36h8128ebf_0
  openssl:             1.0.2p-hfa6e2cd_0
  pip:                 10.0.1-py36_0
  protobuf:            3.6.0-py36he025d50_0
  pyparsing:           2.2.2-py36_0
  pyqt:                5.9.2-py36h6538335_2
  python:              3.6.7-h33f27b4_0
  python-dateutil:     2.7.3-py36_0
  pytz:                2018.5-py36_0
  pyyaml:              3.13-py36hfa6e2cd_0
  qt:                  5.9.6-vc14h1e9a669_2
  scipy:               1.1.0-py36h4f6bf74_1
  setuptools:          40.4.3-py36_0
  sip:                 4.19.8-py36h6538335_0
  six:                 1.11.0-py36_1
  sqlite:              3.25.2-hfa6e2cd_0
  tensorboard:         1.11.0-py36he025d50_0
  tensorflow:          1.11.0-eigen_py36h346fd36_0
  tensorflow-base:     1.11.0-eigen_py36h45df0d8_0
  termcolor:           1.1.0-py36_1
  tornado:             5.1.1-py36hfa6e2cd_0
  vc:                  14.1-h0510ff6_4
  vs2015_runtime:      14.15.26706-h3a45250_0
  werkzeug:            0.14.1-py36_0
  wheel:               0.32.2-py36_0
  wincertstore:        0.2-py36h7fe50ca_0
  yaml:                0.1.7-hc54c509_2
  zlib:                1.2.11-h8395fce_2
  </code></pre>