利用pipenv shell切換到虛擬環境時，顯示報錯：AttributeError: 'module' object has no attribute 'run'
可以看到是d:\program\python34\lib\site-packages\pipenv\shells.py文件的第62行報錯了，提示模塊沒有run的屬性，於是就跑到該文件的第62行去看
選中run，CTRL+B發現能看到源碼，源碼如下：
if sys.version_info >= (3, 6): # Nearly same args as Popen.__init__ except for timeout, input, and check
def run(args: _CMD,
timeout: Optional[float] = ...,
input: Optional[_TXT] = ...,
check: bool = ...,
bufsize: int = ...,
executable: _PATH = ...,
stdin: _FILE = ...,
stdout: _FILE = ...,
stderr: _FILE = ...,
preexec_fn: Callable[[], Any] = ...,
close_fds: bool = ...,
shell: bool = ...,
cwd: Optional[_PATH] = ...,
env: Optional[_ENV] = ...,
universal_newlines: bool = ...,
startupinfo: Any = ...,
creationflags: int = ...,
restore_signals: bool = ...,
start_new_session: bool = ...,
pass_fds: Any = ...,
*,
encoding: Optional[str] = ...,
errors: Optional[str] = ...) -> CompletedProcess: ...
else:
# Nearly same args as Popen.__init__ except for timeout, input, and check
def run(args: _CMD,
timeout: Optional[float] = ...,
input: Optional[_TXT] = ...,
check: bool = ...,
bufsize: int = ...,
executable: _PATH = ...,
stdin: _FILE = ...,
stdout: _FILE = ...,
stderr: _FILE = ...,
preexec_fn: Callable[[], Any] = ...,
close_fds: bool = ...,
shell: bool = ...,
cwd: Optional[_PATH] = ...,
env: Optional[_ENV] = ...,
universal_newlines: bool = ...,
startupinfo: Any = ...,
creationflags: int = ...,
restore_signals: bool = ...,
start_new_session: bool = ...,
pass_fds: Any = ...) -> CompletedProcess: ...
但是請看第一行 if sys.version_info >= (3, 6): ，我們姑且猜測一下，這個3.6就是python的版本號，如果版本大於3.6，就用第一個run函數，否則就用第二個run函數，這兩個函數有什么不同——第一個run函數多了下面兩行
encoding: Optional[str] = ...,
errors: Optional[str] = ...)
可是，既然版本大於3.6和小於3.6都會調用已存在的run函數，那為什么會報錯？我們來看一下比較完整的代碼
不知道有沒有留意到當版本大於3.5時，才會去第二個if里判斷是否大於3.6，而我當前的版本是3.4.4，因此不滿足大於3.5的if判斷，而滿足大於3.3的if判斷，此時下面的方法都是call了(事實上，只要滿足版本<3.5，都應該調用的是call方法)
if sys.version_info >= (3, 5): class CompletedProcess: # morally: _CMD args = ... # type: Any returncode = ... # type: int # morally: Optional[_TXT] stdout = ... # type: Any stderr = ... # type: Any def __init__(self, args: _CMD, returncode: int, stdout: Optional[_TXT] = ..., stderr: Optional[_TXT] = ...) -> None: ... def check_returncode(self) -> None: ... if sys.version_info >= (3, 6): # Nearly same args as Popen.__init__ except for timeout, input, and check def run(args: _CMD, timeout: Optional[float] = ..., input: Optional[_TXT] = ..., check: bool = ..., bufsize: int = ..., executable: _PATH = ..., stdin: _FILE = ..., stdout: _FILE = ..., stderr: _FILE = ..., preexec_fn: Callable[[], Any] = ..., close_fds: bool = ..., shell: bool = ..., cwd: Optional[_PATH] = ..., env: Optional[_ENV] = ..., universal_newlines: bool = ..., startupinfo: Any = ..., creationflags: int = ..., restore_signals: bool = ..., start_new_session: bool = ..., pass_fds: Any = ..., *, encoding: Optional[str] = ..., errors: Optional[str] = ...) -> CompletedProcess: ... else: # Nearly same args as Popen.__init__ except for timeout, input, and check def run(args: _CMD, timeout: Optional[float] = ..., input: Optional[_TXT] = ..., check: bool = ..., bufsize: int = ..., executable: _PATH = ..., stdin: _FILE = ..., stdout: _FILE = ..., stderr: _FILE = ..., preexec_fn: Callable[[], Any] = ..., close_fds: bool = ..., shell: bool = ..., cwd: Optional[_PATH] = ..., env: Optional[_ENV] = ..., universal_newlines: bool = ..., startupinfo: Any = ..., creationflags: int = ..., restore_signals: bool = ..., start_new_session: bool = ..., pass_fds: Any = ...) -> CompletedProcess: ... # Same args as Popen.__init__ if sys.version_info >= (3, 3): # 3.3 added timeout def call(args: _CMD, bufsize: int = ..., executable: _PATH = ..., stdin: _FILE = ..., stdout: _FILE = ..., stderr: _FILE = ..., preexec_fn: Callable[[], Any] = ..., close_fds: bool = ..., shell: bool = ..., cwd: Optional[_PATH] = ..., env: Optional[_ENV] = ..., universal_newlines: bool = ..., startupinfo: Any = ..., creationflags: int = ..., restore_signals: bool = ..., start_new_session: bool = ..., pass_fds: Any = ..., timeout: float = ...) -> int: ... else: def call(args: _CMD, bufsize: int = ..., executable: _PATH = ..., stdin: _FILE = ..., stdout: _FILE = ..., stderr: _FILE = ..., preexec_fn: Callable[[], Any] = ..., close_fds: bool = ..., shell: bool = ..., cwd: Optional[_PATH] = ..., env: Optional[_ENV] = ..., universal_newlines: bool = ..., startupinfo: Any = ..., creationflags: int = ..., restore_signals: bool = ..., start_new_session: bool = ..., pass_fds: Any = ...) -> int: ...
了解這個，就知道如何解決了，只要修改源碼把run換成call即可(如果要使用3.5及以上的版本，建議把call再換回run)
再次使用pipenv shell，發現可以切換到虛擬環境了
參考文章
https://cuiqingcai.com/5846.html