$ pip install scandir
Collecting scandir
  Using cached scandir-1.5.tar.gz
Building wheels for collected packages: scandir
  Running setup.py bdist_wheel for scandir ... error
  Complete output from command /home/ada/.virtualenvs/uapi/bin/python2 -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-mO0hXC/scandir/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" bdist_wheel -d /tmp/tmp7R0mwnpip-wheel- --python-tag cp27:
  running bdist_wheel
  running build
  running build_py
  creating build
  creating build/lib.linux-x86_64-2.7
  copying scandir.py -> build/lib.linux-x86_64-2.7
  running build_ext
  building '_scandir' extension
  creating build/temp.linux-x86_64-2.7
  x86_64-linux-gnu-gcc -pthread -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fno-strict-aliasing -Wdate-time -D_FORTIFY_SOURCE=2 -g -fstack-protector-strong -Wformat -Werror=format-security -fPIC -I/usr/include/python2.7 -c _scandir.c -o build/temp.linux-x86_64-2.7/_scandir.o
  _scandir.c:14:20: fatal error: Python.h: No such file or directory
   #include <Python.h>
                      ^
  compilation terminated.
  error: command 'x86_64-linux-gnu-gcc' failed with exit status 1

  ----------------------------------------
  Failed building wheel for scandir
  Running setup.py clean for scandir
Failed to build scandir
Installing collected packages: scandir
  Running setup.py install for scandir ... error
    Complete output from command /home/ada/.virtualenvs/uapi/bin/python2 -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-mO0hXC/scandir/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record /tmp/pip-7C3Ypx-record/install-record.txt --single-version-externally-managed --compile --install-headers /home/ada/.virtualenvs/uapi/include/site/python2.7/scandir:
    running install
    running build
    running build_py
    creating build
    creating build/lib.linux-x86_64-2.7
    copying scandir.py -> build/lib.linux-x86_64-2.7
    running build_ext
    building '_scandir' extension
    creating build/temp.linux-x86_64-2.7
    x86_64-linux-gnu-gcc -pthread -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fno-strict-aliasing -Wdate-time -D_FORTIFY_SOURCE=2 -g -fstack-protector-strong -Wformat -Werror=format-security -fPIC -I/usr/include/python2.7 -c _scandir.c -o build/temp.linux-x86_64-2.7/_scandir.o
    _scandir.c:14:20: fatal error: Python.h: No such file or directory
     #include <Python.h>
                        ^
    compilation terminated.
    error: command 'x86_64-linux-gnu-gcc' failed with exit status 1

    ----------------------------------------
Command "/home/ada/.virtualenvs/uapi/bin/python2 -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-mO0hXC/scandir/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record /tmp/pip-7C3Ypx-record/install-record.txt --single-version-externally-managed --compile --install-headers /home/ada/.virtualenvs/uapi/include/site/python2.7/scandir" failed with error code 1 in /tmp/pip-build-mO0hXC/scandir/