pyflakes to avoid missing imports

.flake8

@@ -0,0 +1,5 b''
+[flake8]
+ignore = W293,E301,E271,E265,W291,E722,E302,C901,E225,E128,E122,E226,E231
+max-line-length = 160
+exclude = tests/*
+max-complexity = 10

.github/workflows/mypy.yml

@@ -23,8 +23,11 b' jobs:'
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install mypy
+        pip install mypy pyflakes flake8
     - name: Lint with mypy
       run: |
         mypy IPython/terminal/ptutils.py
         mypy IPython/core/c*.py
+    - name: Lint with pyflakes
+      run: |
+        flake8  IPython/core/magics/script.py

IPython/core/magics/script.py

@@ -18,7 +18,6 b' from IPython.core.magic import ('
     Magics, magics_class, line_magic, cell_magic
 )
 from IPython.lib.backgroundjobs import BackgroundJobManager
-from IPython.utils import py3compat
 from IPython.utils.process import arg_split
 from traitlets import List, Dict, default
 
@@ -262,8 +261,7 b' class ScriptMagics(Magics):'
             except OSError:
                 pass
             except Exception as e:
-                print("Error while terminating subprocess (pid=%i): %s" \
-                    % (p.pid, e))
+                print("Error while terminating subprocess (pid=%i): %s" % (p.pid, e))
             return
         if args.raise_error and p.returncode!=0:
             raise CalledProcessError(p.returncode, cell)

MANIFEST.in

@@ -7,6 +7,7 b' include MANIFEST.in'
 include pytest.ini
 include mypy.ini
 include .mailmap
+include .flake8
 
 recursive-exclude tools *
 exclude tools