KeyError: 'builtins'

[nme01]

When I ran mypy using the following command:

mypy -p quant-fin --follow-imports=silent --show-traceback

I got the following error:

qstrader\version.py:1: error: Cannot find module named 'builtins'
Traceback (most recent call last):
  File "c:\users\jacek\appdata\local\programs\python\python35\lib\runpy.py", line 184, in _run_module_as_main
    "__main__", mod_spec)
  File "c:\users\jacek\appdata\local\programs\python\python35\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Scripts\mypy.exe\__main__.py", line 9, in <module>
    sys.exit(console_entry())
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\__main__.py", line 7, in console_entry
    main(None)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\main.py", line 50, in main
    res = type_check_only(sources, bin_dir, options)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\main.py", line 97, in type_check_only
    options=options)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\build.py", line 196, in build
    graph = dispatch(sources, manager)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\build.py", line 1769, in dispatch
    process_graph(graph, manager)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\build.py", line 2012, in process_graph
    process_stale_scc(graph, scc, manager)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\build.py", line 2107, in process_stale_scc
    graph[id].semantic_analysis()
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\build.py", line 1664, in semantic_analysis
    self.manager.semantic_analyzer.visit_file(self.tree, self.xpath, self.options, patches)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\semanal.py", line 295, in visit_file
    self.accept(d)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\semanal.py", line 3636, in accept
    node.accept(self)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\nodes.py", line 565, in accept
    return visitor.visit_func_def(self)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\semanal.py", line 418, in visit_func_def
    self.analyze_function(defn)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\semanal.py", line 598, in analyze_function
    defn.type = self.type_analyzer().visit_callable_type(defn.type, nested=False)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\typeanal.py", line 333, in visit_callable_type
    fallback=t.fallback or self.named_type('builtins.function'),
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\typeanal.py", line 545, in named_type
    node = self.lookup_fqn_func(fully_qualified_name)
  File "C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\site-packages\mypy\semanal.py", line 3482, in lookup_fully_qualified
    n = self.modules[parts[0]]
KeyError: 'builtins'

[gvanrossum]

This is almost always caused by something in the mypy installation. It's not easy to debug without sitting next to you.

[nme01]

I tried installing it using both:
python -m pip install mypy
and
python -m pip install -U git+git://github.com/python/mypy.git.

I am using Windows 10 and Python 3.5.2 (from python.org).
I don't know what other information could be useful for debugging the issue.

[Michael0x2a]

I you can isolate your codebase down into a minimal example that reproduces the problem and share it, that would be helpful.

You can also try re-running mypy with verbose mode enabled: do mypy -p quant-fin --follow-imports=silent --show-traceback -v -v.

Incidentally, does your project have a module or file named builtins? That might be causing some internal conflicts with mypy in some way.

[nme01]

I ran it on a single file, which I've had extracted from the workspace, so that other files don't get imported by accident. It's content:

import datetime


def iso_to_gregorian(iso_year: int, iso_week: int, iso_day: int):
    fourth_jan = datetime.date(iso_year, 1, 4)
    _, fourth_jan_week, fourth_jan_day = fourth_jan.isocalendar()
    return fourth_jan + datetime.timedelta(days=iso_day-fourth_jan_day, weeks=iso_week-fourth_jan_week)

What I've got after running mypy iso_to_gregorian.py --follow-imports=silent --show-traceback -v -v:

LOG:  Mypy version 0.530-dev-b6bcdc0038fa3fbca54190b5b66e5e5d95f67acc
LOG:  Metadata not found for iso_to_gregorian
LOG:  Parsing iso_to_gregorian.py (iso_to_gregorian)
LOG:  Loaded graph with 1 nodes
LOG:  Found 1 SCCs; largest has 1 nodes
TRACE: Priorities for iso_to_gregorian:
LOG:  Processing SCC singleton (iso_to_gregorian) as inherently stale
iso_to_gregorian.py:4: error: INTERNAL ERROR -- please report a bug at https://github.com/python/mypy/issues version: 0.530-dev-b6bcdc0038fa3fbca54190b5b66e5e5d95f67acc
iso_to_gregorian.py:4: note: use --pdb to drop into pdb
LOG:  Build finished in 0.016 seconds with 1 modules, 0 types, and 16 errors

And answering your question:

Incidentally, does your project have a module or file named builtins?

No, it doesn't.

[emmatyping]

@nme01 I have a couple ideas. I've had issues where if I install via pip then install again from git, it can cause conflicts. Can you run python -m pip uninstall mypy and verify that there is not a mypy.exe in C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Scripts? Additionally search for a left over typeshed directory in C:\Users\Jacek\AppData\Local\Programs\Python\Python35\Lib\mypy after uninstalling. If anything is left, delete it. Then try running python-m pip install mypy.

[emmatyping]

@nme01 Could you try python -m pip install git+https://github.com/python/mypy.git that should either: a) fix your installation or b) help us narrow down issues with your install.

[emmatyping]

Solved in #3991