STY,MAINT: avoid 'multiple imports on one line' (flake8 E401)

* PEP 8: "Imports should usually be on separate lines"
* Where modified, sort imported modules alphabetically
* Clean-up unused imports from these expanded lines

11 files changed, 41 insertions, 18 deletions

diff --git a/doc/source/conf.py b/doc/source/conf.py
index 957cb17e6..11be7ec1c 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -1,5 +1,7 @@
 # -*- coding: utf-8 -*-
-import sys, os, re
+import os
+import re
+import sys
 
 # Minimum version, enforced by sphinx
 needs_sphinx = '2.2.0'
diff --git a/doc/summarize.py b/doc/summarize.py
index ea2397538..5a3088267 100755
--- a/doc/summarize.py
+++ b/doc/summarize.py
@@ -5,8 +5,12 @@ summarize.py
 Show a summary about which NumPy functions are documented and which are not.
 
 """
-import os, glob, re, sys, inspect, optparse
 import collections.abc
+import glob
+import inspect
+import optparse
+import os
+import sys
 
 sys.path.append(os.path.join(os.path.dirname(__file__), 'sphinxext'))
 from sphinxext.phantom_import import import_phantom_module
@@ -98,7 +102,11 @@ def check_numpy():
     documented = get_documented(glob.glob(SOURCE_DIR + '/*.rst'))
     undocumented = {}
 
-    import numpy, numpy.fft, numpy.linalg, numpy.random
+    import numpy
+    import numpy.fft
+    import numpy.linalg
+    import numpy.random
+
     for mod in [numpy, numpy.fft, numpy.linalg, numpy.random,
                 numpy.ctypeslib, numpy.emath, numpy.ma]:
         undocumented.update(get_undocumented(documented, mod, skip=SKIP_LIST))
diff --git a/numpy/core/code_generators/genapi.py b/numpy/core/code_generators/genapi.py
index 4fa68a1f0..88dc2d90a 100644
--- a/numpy/core/code_generators/genapi.py
+++ b/numpy/core/code_generators/genapi.py
@@ -8,10 +8,11 @@ specified.
 """
 from numpy.distutils.conv_template import process_file as process_c_file
 
-import sys, os, re
 import hashlib
 import io
-
+import os
+import re
+import sys
 import textwrap
 
 from os.path import join
diff --git a/numpy/core/tests/test_scalarprint.py b/numpy/core/tests/test_scalarprint.py
index 126191856..6502ec4c1 100644
--- a/numpy/core/tests/test_scalarprint.py
+++ b/numpy/core/tests/test_scalarprint.py
@@ -2,9 +2,10 @@
 """ Test printing of scalar types.
 
 """
-import code, sys
+import code
 import platform
 import pytest
+import sys
 
 from tempfile import TemporaryFile
 import numpy as np
diff --git a/numpy/distutils/command/config.py b/numpy/distutils/command/config.py
index 2c833aad7..e54a54449 100644
--- a/numpy/distutils/command/config.py
+++ b/numpy/distutils/command/config.py
@@ -2,11 +2,12 @@
 # try_compile call. try_run works but is untested for most of Fortran
 # compilers (they must define linker_exe first).
 # Pearu Peterson
-import os, signal
-import warnings
-import sys
+import os
+import signal
 import subprocess
+import sys
 import textwrap
+import warnings
 
 from distutils.command.config import config as old_config
 from distutils.command.config import LANG_EXT
diff --git a/numpy/distutils/cpuinfo.py b/numpy/distutils/cpuinfo.py
index e066f9888..7bcda256b 100644
--- a/numpy/distutils/cpuinfo.py
+++ b/numpy/distutils/cpuinfo.py
@@ -14,13 +14,15 @@ Pearu Peterson
 """
 __all__ = ['cpu']
 
-import sys, re, types
 import os
+import platform
+import re
+import sys
+import types
+import warnings
 
 from subprocess import getstatusoutput
 
-import warnings
-import platform
 
 def getoutput(cmd, successful_status=(0,), stacklevel=1):
     try:
diff --git a/numpy/distutils/line_endings.py b/numpy/distutils/line_endings.py
index 92a84e56a..686e5ebd9 100644
--- a/numpy/distutils/line_endings.py
+++ b/numpy/distutils/line_endings.py
@@ -1,7 +1,10 @@
 """ Functions for converting from DOS to UNIX line endings
 
 """
-import sys, re, os
+import os
+import re
+import sys
+
 
 def dos2unix(file):
     "Replace CRLF with LF in argument files.  Print names of changed files."
diff --git a/numpy/doc/constants.py b/numpy/doc/constants.py
index 96813b66c..2c629ad33 100644
--- a/numpy/doc/constants.py
+++ b/numpy/doc/constants.py
@@ -13,7 +13,8 @@ NumPy includes several constants:
 #
 # Note: the docstring is autogenerated.
 #
-import textwrap, re
+import re
+import textwrap
 
 # Maintain same format as in numpy.add_newdocs
 constants = []
diff --git a/numpy/linalg/lapack_lite/clapack_scrub.py b/numpy/linalg/lapack_lite/clapack_scrub.py
index 531d861cf..c5a3279be 100644
--- a/numpy/linalg/lapack_lite/clapack_scrub.py
+++ b/numpy/linalg/lapack_lite/clapack_scrub.py
@@ -1,6 +1,7 @@
 #!/usr/bin/env python
-import sys, os
+import os
 import re
+import sys
 from io import StringIO
 
 from plex import Scanner, Str, Lexicon, Opt, Bol, State, AnyChar, TEXT, IGNORE
diff --git a/numpy/random/tests/test_extending.py b/numpy/random/tests/test_extending.py
index 23a874fb1..b0d4c60fe 100644
--- a/numpy/random/tests/test_extending.py
+++ b/numpy/random/tests/test_extending.py
@@ -1,8 +1,9 @@
-import os, sys
+import os
 import pytest
-import warnings
 import shutil
 import subprocess
+import sys
+import warnings
 
 try:
     import cffi
diff --git a/numpy/testing/_private/utils.py b/numpy/testing/_private/utils.py
index 8b098f1d1..67b7d317c 100644
--- a/numpy/testing/_private/utils.py
+++ b/numpy/testing/_private/utils.py
@@ -1444,7 +1444,9 @@ def _assert_valid_refcount(op):
     """
     if not HAS_REFCOUNT:
         return True
-    import numpy as np, gc
+
+    import gc
+    import numpy as np
 
     b = np.arange(100*100).reshape(100, 100)
     c = b