title: from .cv2 import * ImportError: libgthread-2.0.so.0: cannot open shared object file: No such file or directory
body: <p>I get this error when execute docker file for opencv:</p>
  
  <p><strong>Error:</strong></p>
  
  <pre><code>from .cv2 import * ImportError: libgthread-2.0.so.0: cannot open shared object file: No such file or directory
  </code></pre>
  
  <p><strong>Dockerfile:</strong></p>
  
  <pre><code>FROM jjanzic/docker-python3-opencv
  COPY . /app
  WORKDIR /app
  
  RUN pip3 install -r requirements.txt
  
  
  ENTRYPOINT ["python3"]
  CMD ["app.py"]
  </code></pre>
  
  <p><strong>Requirements.txt</strong></p>
  
  <pre><code>opencv-contrib-python-headless==3.4.3.18
  Click==7.0
  cloudpickle==0.6.1
  cycler==0.10.0
  dask==0.20.1
  decorator==4.3.0
  Flask==1.0.2
  imutils==0.5.1
  itsdangerous==1.1.0
  Jinja2==2.10
  kiwisolver==1.0.1
  MarkupSafe==1.1.0
  networkx==2.2
  numpy==1.15.4
  Pillow==5.3.0
  pyparsing==2.3.0
  python-dateutil==2.7.5
  PyWavelets==1.0.1
  scikit-image==0.14.1
  scipy==1.1.0
  six==1.11.0
  toolz==0.9.0
  Werkzeug==0.14.1
  </code></pre>
  
  <p>Please tell me how to fix it?</p>