  Governance has been highlighted as a key factor in the success of an Open
Source Software (OSS) project. It is generally seen that in a mixed meritocracy
and autocracy governance model, the decision-making (DM) responsibility
regarding what features are included in the OSS is shared among members from
select roles; prominently the project leader. However, less examination has
been made whether members from these roles are also prominent in DM discussions
and how decisions are made, to show they play an integral role in the success
of the project. We believe that to establish their influence, it is necessary
to examine not only discussions of proposals in which the project leader makes
the decisions, but also those where others make the decisions. Therefore, in
this study, we examine the prominence of members performing different roles in:
(i) making decisions, (ii) performing certain social roles in DM discussions
(e.g., discussion starters), (iii) contributing to the OSS development social
network through DM discussions, and (iv) how decisions are made under both
scenarios. We examine these aspects in the evolution of the well-known Python
project. We carried out a data-driven longitudinal study of their email
communication spanning 20 years, comprising about 1.5 million emails. These
emails contain decisions for 466 Python Enhancement Proposals (PEPs) that
document the language's evolution. Our findings make the influence of different
roles transparent to future (new) members, other stakeholders, and more
broadly, to the OSS research community.
