webdriver.Firefox：WebDriverException：消息：“geckodriver”可执行文件需要在 PATH [重复]

Question

这个问题在这里已经有了答案：

WebDriverException: 'geckodriver' 可执行文件需要在 PATH 中，即使它是(1 个回答)

Python 3.5 - “Geckodriver 可执行文件需要在 PATH 中” （4 个回答）

selenium.common.exceptions.WebDriverException：消息：'geckodriver' 可执行文件需要在 GeckoDriver Selenium Firefox 的 PATH 中（2 个回答）

FileNotFoundError：[Errno 2] 没有这样的文件或目录：'geckodriver'：'geckodriver' 在 MAC OS 中使用 GeckoDriver 和 Python （2 个回答）

去年关闭。

>>> from selenium import webdriver
>>> browser = webdriver.Firefox()
**error Traceback** :

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/selenium/webdriver/common/service.py", line 76, in start
    stdin=PIPE)
  File "/usr/lib/python3.7/subprocess.py", line 775, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.7/subprocess.py", line 1522, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'geckodriver': 'geckodriver'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.7/dist-packages/selenium/webdriver/firefox/webdriver.py", line 164, in __init__
    self.service.start()
  File "/usr/local/lib/python3.7/dist-packages/selenium/webdriver/common/service.py", line 83, in start
    os.path.basename(self.path), self.start_error_message)
selenium.common.exceptions.WebDriverException: Message: 'geckodriver' executable needs to be in PATH.