wind@wind-ThinkPad-X250:~/Downloads/PyQt5_gpl-5.12.2$ python3 -m pip install PyQt5
Collecting PyQt5
 Downloading https://files.pythonhosted.org/packages/6a/f4/6a63aafcee3efd2b156dc835d9c85ca99b24e80f8af89b6da5c46054fe43/PyQt5-5.12.2-5.12.3-cp35.cp36.cp37.cp38-abi3-manylinux1_x86_64.whl (61.5MB)
  100% |████████████████████████████████| 61.5MB 18kB/s 
Collecting PyQt5_sip<13,>=4.19.14 (from PyQt5)
 Downloading https://files.pythonhosted.org/packages/08/19/ef6b97cfdbb8f9312d71388384f572706e40bf88f07fffb0fc64846b4a36/PyQt5_sip-4.19.17-cp35-cp35m-manylinux1_x86_64.whl (67kB)
  100% |████████████████████████████████| 71kB 107kB/s 
Installing collected packages: PyQt5-sip, PyQt5
Successfully installed PyQt5-5.12.2 PyQt5-sip-4.19.17
You are using pip version 8.1.1, however version 19.1.1 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.
wind@wind-ThinkPad-X250:~/Downloads/PyQt5_gpl-5.12.2$ 

> import sys
> sys.modules.keys()
dict_keys(['problem_report', '_bz2', 'email.feedparser', 'email.mime', 'base64', 'select', 'tarfile', '__future__', '_compat_pickle', 'importlib.util', 'mpl_toolkits', 'json.scanner', 'signal', 'json', 're', 'subprocess', 'ipaddress', 'configparser', '_functools', 'bz2', 'uu', 'pyexpat', 'copyreg', '__main__', 'selectors', 'apt.package', 'PyQt5', 'xml', 'pyexpat.errors', '_json', '_thread', 'email.message', 'apt.cdrom', 'calendar', 'importlib.abc', 'textwrap', 'random', 'email.mime.text', 'email._encoded_words', 'email._parseaddr', 'shutil', 'atexit', 'sre_parse', '_frozen_importlib_external', 'importlib.machinery', '_compression', 'zlib', 'copy', 'fcntl', '_weakref', 'sitecustomize', 'collections.abc', 'apport_python_hook', 'email.header', 'email.errors', '_io', '_operator', 'email.encoders', '_string', 'contextlib', '_frozen_importlib', '_pickle', 'apt.cache', 'token', '_signal', '_collections_abc', 'email._policybase', 'apt.progress', 'encodings.utf_8', 'genericpath', '_hashlib', 'heapq', '_socket', '_stat', 'site', 'sysconfig', 'xml.dom.minicompat', 'socket', '_struct', 'string', 'email.charset', 'importlib', 'pyexpat.model', 'gzip', 'codecs', '_warnings', 'apport.packaging_impl', 'threading', 'encodings', 'builtins', 'enum', 'binascii', 'http', 'itertools', 'operator', '_ssl', 'xml.parsers.expat', '_datetime', 'glob', '_locale', '_random', 'apport.fileutils', 'xml.dom.NodeFilter', '_posixsubprocess', 'abc', 'urllib.error', 'datetime', 'sre_constants', 'json.encoder', 'encodings.aliases', 'reprlib', '_weakrefset', 'json.decoder', 'importlib._bootstrap_external', 'sre_compile', 'email.mime.base', 'email.parser', 'math', 'keyword', 'encodings.latin_1', 'linecache', '_heapq', 'urllib', 'apport', 'tokenize', 'importlib._bootstrap', 'urllib.response', 'xml.parsers.expat.errors', 'apport.report', 'apport.packaging', 'posixpath', 'gettext', 'xml.dom.xmlbuilder', 'xml.dom', 'pwd', 'os', '_sysconfigdata_m', '_sitebuiltins', 'errno', 'xml.parsers.expat.model', 'os.path', '_sysconfigdata', '_sre', 'email.mime.multipart', 'collections', 'apt.progress.base', 'traceback', 'apt', 'io', 'weakref', 'urllib.request', 'hashlib', 'email.iterators', 'quopri', 'http.client', 'zipimport', '_imp', 'sys', 'rlcompleter', '_bootlocale', 'locale', 'urllib.parse', 'fnmatch', 'tempfile', 'xml.dom.domreg', '_codecs', 'bisect', 'email.utils', 'email.mime.nonmultipart', '_bisect', 'stat', 'warnings', 'ssl', 'functools', 'email', 'grp', '_lzma', 'email.quoprimime', 'struct', 'apt.progress.text', 'time', 'xml.parsers', 'email.base64mime', 'apt_pkg', 'pickle', 'imp', 'types', 'xml.dom.minidom', 'lzma', 'marshal', '_collections', 'readline', 'posix'])
> 

wind@wind-ThinkPad-X250:~$ sudo python3 -m pip uninstall PyQt5
[sudo] password for wind: 
WARNING: The directory '/home/wind/.cache/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
Uninstalling PyQt5-5.12.2:
 Would remove:
  /home/wind/.local/bin/pylupdate5
  /home/wind/.local/bin/pyrcc5
  /home/wind/.local/bin/pyuic5
  /home/wind/.local/lib/python3.5/site-packages/PyQt5-5.12.2.dist-info/*
  /home/wind/.local/lib/python3.5/site-packages/PyQt5/*
 Would not remove (might be manually added):
  /home/wind/.local/lib/python3.5/site-packages/PyQt5/sip.so
Proceed (y/n)"htmlcode">

#!/bin/env python3 
# -*- coding: utf-8 -*- 
 
import sys
from PyQt5.QtWidgets import QApplication, QWidget  #导入相应的包
 
if __name__ == '__main__':
 
   app = QApplication(sys.argv)     #创建QApplication对象是必须，管理整个>程序，参数可有可无，有的话可接收命令行参数
 
   w = QWidget()            #创建窗体对象，
   w.resize( 250, 150 )         #设置窗体大小
   w.move( 100, 300 )          #设置在屏幕上的显示位置
   w.setWindowTitle( 'Simple' )     #设置窗口标题
   w.show()               #窗口显示
 
   sys.exit( app.exec_() )