Docker-airflow: Permission Error: pip install cmake

[Paw2Pom]

I have tried to install cmake as some pip packages require it, however I have run into permission error as follow:

=====

airflow@webserver:~$ pip install cmake
Collecting cmake
Downloading cmake-0.9.0-cp36-cp36m-manylinux1_x86_64.whl (20.2MB)
100% |████████████████████████████████| 20.2MB 90kB/s
Installing collected packages: cmake
Exception:
Traceback (most recent call last):
File "/usr/local/lib/python3.6/site-packages/pip/basecommand.py", line 215, in main
status = self.run(options, args)
File "/usr/local/lib/python3.6/site-packages/pip/commands/install.py", line 342, in run
prefix=options.prefix_path,
File "/usr/local/lib/python3.6/site-packages/pip/req/req_set.py", line 784, in install
**kwargs
File "/usr/local/lib/python3.6/site-packages/pip/req/req_install.py", line 851, in install
self.move_wheel_files(self.source_dir, root=root, prefix=prefix)
File "/usr/local/lib/python3.6/site-packages/pip/req/req_install.py", line 1064, in move_wheel_files
isolated=self.isolated,
File "/usr/local/lib/python3.6/site-packages/pip/wheel.py", line 345, in move_wheel_files
clobber(source, lib_dir, True)
File "/usr/local/lib/python3.6/site-packages/pip/wheel.py", line 316, in clobber
ensure_dir(destdir)
File "/usr/local/lib/python3.6/site-packages/pip/utils/__init__.py", line 83, in ensure_dir
os.makedirs(path)
File "/usr/local/lib/python3.6/os.py", line 220, in makedirs
mkdir(name, mode)
PermissionError: [Errno 13] Permission denied: '/usr/local/lib/python3.6/site-packages/cmake-0.9.0.dist-info'

[Paw2Pom]

I found the solution, just use this: $(which pip) install --user cmake