@Substitution(name='<STR_LIT>')<EOL><INDENT>@Appender(_common_see_also)<EOL>def expanding(self, *args, **kwargs):<DEDENT>
from pandas.core.window import ExpandingGroupby<EOL>return ExpandingGroupby(self, *args, **kwargs)<EOL>
Return an expanding grouper, providing expanding
functionality per group.