code: def initpkg(pkgname, exportdefs, attr=None, eager=False):
      
      attr = attr or {}
      oldmod = sys.modules.get(pkgname)
      d = {}
      f = getattr(oldmod, '__file__', None)
      if f:
          f = _py_abspath(f)
      d['__file__'] = f
      if hasattr(oldmod, '__version__'):
          d['__version__'] = oldmod.__version__
      if hasattr(oldmod, '__loader__'):
          d['__loader__'] = oldmod.__loader__
      if hasattr(oldmod, '__path__'):
          d['__path__'] = [_py_abspath(p) for p in oldmod.__path__]
      if hasattr(oldmod, '__package__'):
          d['__package__'] = oldmod.__package__
      if '__doc__' not in exportdefs and getattr(oldmod, '__doc__', None):
          d['__doc__'] = oldmod.__doc__
      d.update(attr)
      if hasattr(oldmod, "__dict__"):
          oldmod.__dict__.update(d)
      mod = ApiModule(pkgname, exportdefs, implprefix=pkgname, attr=d)
      sys.modules[pkgname] = mod
      # eagerload in bypthon to avoid their monkeypatching breaking packages
      if 'bpython' in sys.modules or eager:
          for module in list(sys.modules.values()):
              if isinstance(module, ApiModule):
                  module.__dict__
docs: initialize given package from the export definitions.