“…The international pedagogical community actively discusses mathematics teachers' professional training and assessments of teachers' competencies. Modern international publications cover current issues of teachers' knowledge and skills (Shulman, 2013;Potari, 2016;Tatto, 2012;Tatto, 2008;Hilligus, 2009); content and structure of professional development of teachers (Hoth, 2017;Hoth, 2017;Buchholtz, 2018;Ingvarson, 2013); models of development of mathematics teachers' methodical competences (Hilligus, 2009;Baumert, 2013;Kunter, 2011;Schwarz, 2019); development of professional identities of future mathematics teachers (Hilligus, 2009;Erens, 2019); pedagogical experience and its impact on the mathematics teachers' development of skills (Li, 2012;Matos, 2009;Potari, 2019;Strutchens, 2017), ect.…”