Question

One can create dictionaries using generators (PEP-289):

dict((h,h*2) for h in range(5))
#{0: 0, 1: 2, 2: 4, 3: 6, 4: 8}

Is it syntactically possible to add some extra key-value pairs in the same dict() call? The following syntax is incorrect but better explains my question:

dict((h,h*2) for h in range(5), {'foo':'bar'})
#SyntaxError: Generator expression must be parenthesized if not sole argument

In other words, is it possible to build the following in a single dict() call:

{0: 0, 1: 2, 2: 4, 3: 6, 4: 8, 'foo': 'bar' }

Answer 1

Constructor:

dict(iterableOfKeyValuePairs, **dictOfKeyValuePairs)

Example:

>>> dict(((h,h*2) for h in range(5)), foo='foo', **{'bar':'bar'})
{0: 0, 1: 2, 2: 4, 3: 6, 4: 8, 'foo': 'foo', 'bar': 'bar'}

(Note that you will need to parenthesize generator expressions if not the sole argument.)