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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 read_version(group):
 """Return the h5features version of a given HDF5 `group`. Look for a 'version' attribute in the `group` and return its value. Return '0.1' if the version is not found. Raises an IOError if it is not supported. """

    version = ('0.1' if 'version' not in group.attrs
               else group.attrs['version'])

    # decode from bytes to str if needed
    if isinstance(version, bytes):
        version = version.decode()

    if not is_supported_version(version):
        raise IOError('version {} is not supported'.format(version))

    return version