code: def p_block_statements(self, p):
          'block_statements : block_statements block_statement'
          p[0] = p[1] + (p[2],)
          p.set_lineno(0, p.lineno(1)f p_block_statements(self, p):
          'block_statements : block_statements block_statement'
          p[0] = p[1] + (p[2],)
          p.set_lineno(0, p.lineno(1))
docs: block_statements : block_statements block_statement