I use cookbook and make steps from it. i updated my ubuntu to 18.4 and performed steps till this

$ virtualenv -p python3 ~/odoo-12.0 

here i get mistake

$ virtualenv -p python3 ~/odoo-12.0
Already using interpreter /usr/bin/python3
Using base prefix '/usr'
New python executable in /home/pena/odoo-12.0/bin/python3
Not overwriting existing python script /home/pena/odoo-12.0/bin/python (you must use /home/pena/odoo-12.0/bin/python3)
Installing setuptools, pkg_resources, pip, wheel...
Complete output from command /home/pena/odoo-12.0/bin/python3 - setuptools pkg_resources pip wheel:
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
/home/pena/odoo-12.0/share/python-wheels/requests-2.18.4-py2.py3-none-any.whl/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.13.1) or chardet (2.3.0) doesn't match a supported version!
Traceback (most recent call last):
File "/usr/share/python-wheels/pip-9.0.1-py2.py3-none-any.whl/pip/__init__.py", line 22, in
ModuleNotFoundError: No module named 'pip._vendor.requests'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "", line 7, in
File "/usr/share/python-wheels/pip-9.0.1-py2.py3-none-any.whl/pip/__init__.py", line 24, in
ImportError: cannot import name 'DependencyWarning'
----------------------------------------
...Installing setuptools, pkg_resources, pip, wheel...done.
Traceback (most recent call last):
File "/usr/bin/virtualenv", line 11, in load_entry_point('virtualenv==15.1.0', 'console_scripts', 'virtualenv')() File "/usr/lib/python3/dist-packages/virtualenv.py", line 724, in main symlink=options.symlink) File "/usr/lib/python3/dist-packages/virtualenv.py", line 992, in create_environment download=download, File "/usr/lib/python3/dist-packages/virtualenv.py", line 922, in install_wheel call_subprocess(cmd, show_stdout=False, extra_env=env, stdin=SCRIPT) File "/usr/lib/python3/dist-packages/virtualenv.py", line 817, in call_subprocess % (cmd_desc, proc.returncode))OSError: Command /home/pena/odoo-12.0/bin/python3 - setuptools pkg_resources pip wheel failed with error code 1​

how to repair it