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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 delete_policy_version(policy_name, version_id,
                  region=None, key=None, keyid=None, profile=None):
    '''
    Delete a policy version.

    CLI Example:

    .. code-block:: bash

        salt myminion boto_iam.delete_policy_version mypolicy v1
    '''
    conn = _get_conn(region=region, key=key, keyid=keyid, profile=profile)

    policy_arn = _get_policy_arn(policy_name, region, key, keyid, profile)
    if not policy_version_exists(policy_arn, version_id, region, key, keyid, profile):
        return True
    try:
        conn.delete_policy_version(policy_arn, version_id)
        log.info('Deleted IAM policy %s version %s.', policy_name, version_id)
    except boto.exception.BotoServerError as e:
        aws = __utils__['boto.get_error'](e)
        log.debug(aws)
        log.error('Failed to delete IAM policy %s version %s: %s',
                  policy_name, version_id, aws.get('message'))
        return False
    return True