Error compiling VS2013 update 5

[anonymous]

C:\boost_1_59_0_2013\boost/bind/bind.hpp(305) : error C2664: 'bool (const boost: :python::api::object &,std::string &)' : cannot convert argument 2 from 'const s td::string' to 'std::string &'

Conversion loses qualifiers C:\boost_1_59_0_2013\boost/bind/bind.hpp(907) : see reference to functio

n template instantiation 'R boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>

::operator ()<bool,bool(cdecl *)(const boost::python::api::object &,std::stri

ng &),boost::_bi::list1<const std::basic_string<char,std::char_traits<char>,std: :allocator<char>> &>>(boost::_bi::type<bool>,F &,A &,long)'