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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 copy_snapshot(kwargs=None, call=None):
    '''
    Copy a snapshot
    '''
    if call != 'function':
        log.error(
            'The copy_snapshot function must be called with -f or --function.'
        )
        return False

    if 'source_region' not in kwargs:
        log.error('A source_region must be specified to copy a snapshot.')
        return False

    if 'source_snapshot_id' not in kwargs:
        log.error('A source_snapshot_id must be specified to copy a snapshot.')
        return False

    if 'description' not in kwargs:
        kwargs['description'] = ''

    params = {'Action': 'CopySnapshot'}

    if 'source_region' in kwargs:
        params['SourceRegion'] = kwargs['source_region']

    if 'source_snapshot_id' in kwargs:
        params['SourceSnapshotId'] = kwargs['source_snapshot_id']

    if 'description' in kwargs:
        params['Description'] = kwargs['description']

    log.debug(params)

    data = aws.query(params,
                     return_url=True,
                     location=get_location(),
                     provider=get_provider(),
                     opts=__opts__,
                     sigver='4')
    return data