Python – SSLError using pip install (to install tensorflow)

There isn't a built-in flag yet, but you can use

pip list --outdated --format=freeze | grep -v '^\-e' | cut -d = -f 1  | xargs -n1 pip install -U

Note: there are infinite potential variations for this. I'm trying to keep this answer short and simple, but please do suggest variations in the comments!

In older version of pip, you can use this instead:

pip freeze --local | grep -v '^\-e' | cut -d = -f 1  | xargs -n1 pip install -U

The grep is to skip editable ("-e") package definitions, as suggested by @jawache. (Yes, you could replace grep+cut with sed or awk or perl or...).

The -n1 flag for xargs prevents stopping everything if updating one package fails (thanks @andsens).

key is just a variable name.

for key in d:

will simply loop over the keys in the dictionary, rather than the keys and values. To loop over both key and value you can use the following:

For Python 3.x:

for key, value in d.items():

For Python 2.x:

for key, value in d.iteritems():

To test for yourself, change the word key to poop.

In Python 3.x, iteritems() was replaced with simply items(), which returns a set-like view backed by the dict, like iteritems() but even better. This is also available in 2.7 as viewitems().

The operation items() will work for both 2 and 3, but in 2 it will return a list of the dictionary's (key, value) pairs, which will not reflect changes to the dict that happen after the items() call. If you want the 2.x behavior in 3.x, you can call list(d.items()).