fix bugs in builtins/2.7/*.pyi

builtins/2.7/posix.pyi

@@ -1,4 +1,4 @@
-from typing import List, Mapping, Tuple, Union, Sequence, IO, Any, Optional
+from typing import List, Mapping, Tuple, Union, Sequence, IO, Optional, TypeVar
 
 error = OSError
 
@@ -110,7 +110,7 @@ def fchdir(fd: int) -> None: ...
 def fchmod(fd: int, mode: int) -> None: ...
 def fchown(fd: int, uid: int, gid: int) -> None: ...
 def fdatasync(fd: int) -> None: ...
-def fdopen(fd: int, mode: str = ..., bufsize: int = ...) -> file: ...
+def fdopen(fd: int, mode: str = ..., bufsize: int = ...) -> IO[str]: ...
 def fork() -> int:
     raise OSError()
 def forkpty() -> Tuple[int, int]:
@@ -143,8 +143,8 @@ def kill(pid: int, sig: int) -> None: ...
 def killpg(pgid: int, sig: int) -> None: ...
 def lchown(path: unicode, uid: int, gid: int) -> None: ...
 def link(source: unicode, link_name: str) -> None: ...
-_t = TypeVar
-def listdir(path: _t) -> List[_t]: ...
+_T = TypeVar("_T")
+def listdir(path: _T) -> List[_T]: ...
 def lseek(fd: int, pos: int, how: int) -> None: ...
 def lstat(path: unicode) -> stat_result: ...
 def major(device: int) -> int: ...
@@ -158,10 +158,10 @@ def open(file: unicode, flags: int, mode: int = ...) -> int: ...
 def openpty() -> Tuple[int, int]: ...
 def pathconf(path: unicode, name: str) -> str: ...
 def pipe() -> Tuple[int, int]: ...
-def popen(command: str, mode: str = ..., bufsize: int = ...) -> file: ...
+def popen(command: str, mode: str = ..., bufsize: int = ...) -> IO[str]: ...
 def putenv(varname: str, value: str) -> None: ...
 def read(fd: int, n: int) -> str: ...
-def readlink(path: _t) -> _t: ...
+def readlink(path: _T) -> _T: ...
 def remove(path: unicode) -> None: ...
 def rename(src: unicode, dst: unicode) -> None: ...
 def rmdir(path: unicode) -> None: ...
@@ -179,7 +179,7 @@ def setsid() -> None: ...
 def setuid(pid: int) -> None: ...
 def stat(path: unicode) -> stat_result: ...
 def statvfs(path: unicode) -> statvfs_result: ...
-def stat_float_times(fd: int) -> NoneType: ...
+def stat_float_times(fd: int) -> None: ...
 def strerror(code: int) -> str: ...
 def symlink(source: unicode, link_name: unicode) -> None: ...
 def sysconf(name: Union[str, int]) -> int: ...
@@ -187,7 +187,7 @@ def system(command: unicode) -> int: ...
 def tcgetpgrp(fd: int) -> int: ...
 def tcsetpgrp(fd: int, pg: int) -> None: ...
 def times() -> Tuple[float, float, float, float, float]: ...
-def tmpfile() -> file: ...
+def tmpfile() -> IO[str]: ...
 def ttyname(fd: int) -> str: ...
 def umask(mask: int) -> int: ...
 def uname() -> Tuple[str, str, str, str, str]: ...