def get_partitions(self,<EOL>database_name,<EOL>table_name,<EOL>expression='<STR_LIT>',<EOL>page_size=None,<EOL>max_items=None):
config = {<EOL>'<STR_LIT>': page_size,<EOL>'<STR_LIT>': max_items,<EOL>}<EOL>paginator = self.get_conn().get_paginator('<STR_LIT>')<EOL>response = paginator.paginate(<EOL>DatabaseName=database_name,<EOL>TableName=table_name,<EOL>Expression=expression,<EOL>PaginationConfig=config<EOL>)<EOL>partitions = set()<EOL>for page in response:<EOL><INDENT>for p in page['<STR_LIT>']:<EOL><INDENT>partitions.add(tuple(p['<STR_LIT>']))<EOL><DEDENT><DEDENT>return partitions<EOL>
Retrieves the partition values for a table.

:param database_name: The name of the catalog database where the partitions reside.
:type database_name: str
:param table_name: The name of the partitions' table.
:type table_name: str
:param expression: An expression filtering the partitions to be returned.
    Please see official AWS documentation for further information.
    https://docs.aws.amazon.com/glue/latest/dg/aws-glue-api-catalog-partitions.html#aws-glue-api-catalog-partitions-GetPartitions
:type expression: str
:param page_size: pagination size
:type page_size: int
:param max_items: maximum items to return
:type max_items: int
:return: set of partition values where each value is a tuple since
    a partition may be composed of multiple columns. For example:
    ``{('2018-01-01','1'), ('2018-01-01','2')}``