 Complete the following phrase:  In 1939-1945 the chief exponent of Czechoslovakism was the London-based Czechoslovak government in exile led by Jan Šrámek and especially by the president in-exile, Edvard Beneš; Czechoslovakism was popular also among some sympathetic British historians, like Seton-Watson. Officially the exile Czechoslovak structures not only refused to recognise the post-September-1938 political changes but they also stuck to the theory of one, Czechoslovak nation; it was advanced as late as in mid-1943. When negotiating with Moscow-sponsored Czechoslovak Communists Beneš advocated return to Czechoslovakism as to a state doctrine, though KSČ at that time was already highly sceptical about viability of the concept. Also the SNR, underground body formed in Slovakia, styled as continuation of the pre-1939 autonomous Slovak assembly, politically heterogeneous though strongly left-leaning and declaring loyalty to president Benes, adopted a different position. The body, formally the supreme political organisation leading the 