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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 get_qemu_version(qemu_path):
 """ Gets the Qemu version. :param qemu_path: path to Qemu executable. """


        if sys.platform.startswith("win"):
            # Qemu on Windows doesn't return anything with parameter -version
            # look for a version number in version.txt file in the same directory instead
            version_file = os.path.join(os.path.dirname(qemu_path), "version.txt")
            if os.path.isfile(version_file):
                try:
                    with open(version_file, "rb") as file:
                        version = file.read().decode("utf-8").strip()
                        match = re.search("[0-9\.]+", version)
                        if match:
                            return version
                except (UnicodeDecodeError, OSError) as e:
                    log.warn("could not read {}: {}".format(version_file, e))
            return ""
        else:
            try:
                output = yield from subprocess_check_output(qemu_path, "-version")
                match = re.search("version\s+([0-9a-z\-\.]+)", output)
                if match:
                    version = match.group(1)
                    return version
                else:
                    raise QemuError("Could not determine the Qemu version for {}".format(qemu_path))
            except subprocess.SubprocessError as e:
                raise QemuError("Error while looking for the Qemu version: {}".format(e))