I think it has to do with turning your one query with 4 inline parts into one query with multiple parts per line. The executemany(...) may have to do additional processing to strip whitespace, newlines and tabs to ensure that it compresses correctly to the original statement (more than just rearranging the string but additional vulnerabilities, idk). If you want to write it that way, do the string processing yourself before hand with split and join. Or,
From here: Use implicit continuation, it's more elegant:
def f():
s = ('123'
'456')
return s
....you can see if this method is any faster.