Able to reference functions but, not classes from a Namespace

I am able to reference functions from a namespace but, not classes. Here is the namespace file SeqLib/FermiAssembler.h"

#ifndef SEQLIB_FERMI_H
#define SEQLIB_FERMI_H

#include <string>
#include <cstdlib>
#include <iostream>

namespace SeqLib 
{

    void print_my_name(){ std::cout << "It's Crt" }
    class FermiAssembler {
    public:
        FermiAssembler();
    };
}

I am able to call print_my_name() via SeqLib::print_my_name() but, not able to reference the FermiAssembler class via SeqLib::FermiAssembler f

What is the problem?