code: def test_subclass_print_method__ns():
      class MyPrinter(CXX11CodePrinter):
          _ns = "my_library::"
  
      p = CXX11CodePrinter()
      myp = MyPrinter()
  
      assert p.doprint(log1p(x)) == "std::log1p(x)"
      assert myp.doprint(log1p(x)) == "my_library::log1p(x)"
  
file_path: sympy/sympy/printing/tests/test_cxx.py
imports: from sympy.core.numbers import Float, Integer, Rational
  from sympy.core.symbol import symbols
  from sympy.functions import beta, Ei, zeta, Max, Min, sqrt, riemann_xi, frac
  from sympy.printing.cxx import CXX98CodePrinter, CXX11CodePrinter, CXX17CodePrinter, cxxcode
  from sympy.codegen.cfunctions import log1p
label_desc: Use image node_id 4 for calling a global function with example usage: test_subclass_print_method__ns() without return types