in bash, how to dynamically write use k and v from variable k and v?

we have an arbitrary number of files that I know they have this format

export k="v"

and I know that k does not contain and = sign. I want to treat k as a delimiter.

0.txt

export a="x=y ==\n=/n/ //a=\n:=dd"

1.txt

export b="====x\\nn/ //y=\n:=dd"

2.txt

export My_key="my-value"

etc!

I want to iterate over the files and do these:

• source the file
• get the key (everything before the first = sign)
• get the value
• create a file named the key from the first step and populate the file with the value from the second step above - The source of truth for the value is the value coming from the env as a result of running the source command

bash.sh file

#!/bin/bashINPUT_DIR="input"OUTPUT_DIR="output"for filename in "$INPUT_DIR"/*; do    source "$filename"    # the three lines below is something I tried and it did not work    # key=$(cat "$filename" | cut -d '=' -f 1 | cut -d '' -f 2)    # value=$(eval echo "\$$key")    # printf "%s" "$VALUE" > "$OUTPUT_DIR/$key"donepython3 test.py

test.py

import osa_env, a_file =  os.environ["a"], open("output" +"/" +"a", "r").read()b_env, b_file =  os.environ["b"], open("output" +"/" +"b", "r").read()Mykey_env, Mykey_file =  os.environ["My_key"], open("output" +"/" +"My_key", "r").read()assert a_env == a_fileassert b_env == b_fileassert Mykey_env == Mykey_file

How can I make it work? The context is that some sidecar container is injecting secrets into files named 0, 1, 2, 3, etc in the input directory with the format of export k="v" - I want those to be available both as an env variable and file and I want the file name to be the key

remember that the source of truth for the value is from env after running the source