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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 list_server_certificates(path_prefix='/', region=None, key=None, keyid=None, profile=None):
    '''
    Lists the server certificates stored in IAM that have the specified path prefix.

    .. versionadded:: ???

    :param path_prefix:
        The path prefix for filtering the results.  For example:  /company/servercerts would get
        all server certificates for which the path starts with /company/servercerts .
        This parameter is optional.  If it is not included, it defaults to a slash (/), listing all
        server certificates.  This parameter allows (per its regex pattern) a string of characters
        consisting of either a forward slash (/) by itself or a string that must begin and end with
        forward slashes.  In addition, it can contain any ASCII character from the ! (u0021)
        through the DEL character (u007F), including most punctuation characters, digits, and upper
        and lowercased letters.

    CLI Example:

    .. code-block:: bash

        salt myminion boto_iam.list_server_certificates path_prefix=/somepath/
    '''
    retries = 10
    sleep = 6
    conn = __utils__['boto3.get_connection']('iam', region=region, key=key, keyid=keyid,
            profile=profile)
    Items = []
    while retries:
        try:
            log.debug('Garnering list of IAM Server Certificates')
            IsTruncated = True
            while IsTruncated:
                kwargs = {'PathPrefix': path_prefix}
                ret = conn.list_server_certificates(**kwargs)
                Items += ret.get('ServerCertificateMetadataList', [])
                IsTruncated = ret.get('IsTruncated')
                kwargs.update({'Marker': ret.get('Marker')})
            return Items
        except botocore.exceptions.ParamValidationError as err:
            raise SaltInvocationError(str(err))
        except botocore.exceptions.ClientError as err:
            if retries and jmespath.search('Error.Code', err.response) == 'Throttling':
                retries -= 1
                log.debug('Throttled by AWS API, retrying in %s seconds...', sleep)
                time.sleep(sleep)
                continue
            log.error('Failed to list IAM Server Certificates: %s', err.message)
            return None