Is there a python script that translate a multi-fasta file that contains DNA sequences to amino acid sequences and save the results in a file.
Did you try to write something?
They are plenty of examples online:
Python Script To Translate Rna Sequences To Protein Sequences
They could be used with a little bit of work on the format of the input.
Whatever script you choose, be sure you use the correct codon table
Maybe in the Biopython tutorial you can find an answer in Chapter 3.9 Translation: