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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def update_version_in_files(current_version: str, new_version: str, files: list):
 """Change old version to the new one in every file given. Note that this version is not the tag formatted one. So for example, your tag could look like `v1.0.0` while your version in the package like `1.0.0`. """

    for filepath in files:
        # Read in the file
        with open(filepath, "r") as file:
            filedata = file.read()

        # Replace the target string
        filedata = filedata.replace(current_version, new_version)

        # Write the file out again
        with open(filepath, "w") as file:
            file.write(filedata)