python format function with { }

Question

Is there a way I can get this output using the format function

name1 = 'test1'
name2 = 'test2'
ps_script = """powershell.exe Start-Job -ScriptBlock {D:\abc\abc\abc\abc.ps1 {} {} abc}""".format(name1,name2)
print(ps_script)

Output Error :

Traceback (most recent call last): File "main.py", line 6, in ps_script = """powershell.exe Start-Job -ScriptBlock {D:\abc\abc\abc\abc.ps1 {} {} abc}""".format(name1,name2) KeyError: 'D'

Expecting output powershell.exe Start-Job -ScriptBlock {D:\abc\abc\abc\abc.ps1 test1 test2 abc}

`ps_script = """powershell.exe Start-Job -ScriptBlock {{D:\abc\abc\abc\abc.ps1 {} {} abc}}""".format(name1,name2) `? — Rakesh, Apr 23 '19 at 13:52
Don't use string formatting to create a command line. Use a tool that lets you pass a *list* of arguments rather than a single line to be processed by a shell. — chepner, Apr 23 '19 at 13:56
Possible duplicate of [How can I print literal curly-brace characters in python string and also use .format on it?](https://stackoverflow.com/questions/5466451/how-can-i-print-literal-curly-brace-characters-in-python-string-and-also-use-fo) — Rick, Apr 23 '19 at 13:57

score 3 · Answer 1 · answered Apr 23 '19 at 13:52

You need to escape to get the literal chars:

name1 = 'test1'
name2 = 'test2'
ps_script = """powershell.exe Start-Job -ScriptBlock {{D:\\abc\\abc\\abc\\abc.ps1 {} {} abc}}""".format(name1,name2)
print(ps_script)

OUTPUT:

powershell.exe Start-Job -ScriptBlock {D:\abc\abc\abc\abc.ps1 test1 test2 abc}

score 0 · Answer 2 · answered Apr 23 '19 at 13:52

0

Use double {{ to get the literal {

ps_script = """powershell.exe Start-Job -ScriptBlock {{D:\abc\abc\abc\abc.ps1 {} {} abc}}""".format(name1,name2)

answered Apr 23 '19 at 13:52

rdas

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Rick · Answer 3 · 2019-04-23T15:18:49.183

Instead of creating a string to run a command like this, you may want to consider using subprocess.run() with a list of arguments (as chepner suggested in the comments) instead.

Maybe like this (notice I added an r to make it a raw string; you want to do this when you are entering backslashes so they aren't interpreted as escape characters):

from subprocess import run

cmds_start = r'powershell.exe Start-Job -ScriptBlock {D:\abc\abc\abc\abc.ps1 abc}'.split()
names = 'test1 test2'.split()

cmds = cmds_start[:-1] + names + cmds_start[-1:]

run(cmds)  # use commands list to run, not string

# but can still view the script like:
print(" ".join(cmds))  # or:
print(*cmds, sep=" ")

python format function with { }

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