I am trying to install deeptools, but I always get the following error:

Collecting deeptools
  Using cached https://files.pythonhosted.org/packages/f6/f3/789edda975fcca4736fab2007d82cab2e86739901c88bb0528db5c338d1f/deepTools-3.5.0.tar.gz
Collecting numpy>=1.9.0 (from deeptools)
  Using cached https://files.pythonhosted.org/packages/3a/5f/47e578b3ae79e2624e205445ab77a1848acdaa2929a00eeef6b16eaaeb20/numpy-1.16.6-cp27-cp27mu-manylinux1_x86_64.whl
Collecting scipy>=0.17.0 (from deeptools)
  Using cached https://files.pythonhosted.org/packages/24/40/11b12af7f322c1e20446c037c47344d89bab4922b8859419d82cf56d796d/scipy-1.2.3-cp27-cp27mu-manylinux1_x86_64.whl
Collecting matplotlib>=3.1.0 (from deeptools)
  Could not find a version that satisfies the requirement matplotlib>=3.1.0 (from deeptools) (from versions: 0.86, 0.86.1, 0.86.2, 0.91.0, 0.91.1, 1.0.1, 1.1.0, 1.1.1, 1.2.0, 1.2.1, 1.3.0, 1.3.1, 1.4.0, 1.4.1rc1, 1.4.1, 1.4.2, 1.4.3, 1.5.0, 1.5.1, 1.5.2, 1.5.3, 2.0.0b1, 2.0.0b2, 2.0.0b3, 2.0.0b4, 2.0.0rc1, 2.0.0rc2, 2.0.0, 2.0.1, 2.0.2, 2.1.0rc1, 2.1.0, 2.1.1, 2.1.2, 2.2.0rc1, 2.2.0, 2.2.2, 2.2.3, 2.2.4, 2.2.5)
No matching distribution found for matplotlib>=3.1.0 (from deeptools)

I run the following command: pip install deeptools

Thanks for your help.