human
I wrote the below code

    def getter(self):
        try:
            if ((header in self.headers) or even_if_nonexistent):
                return cls(self.headers.get(header))
        except ValueError:
            return None
    def setter(self, value):
        self.headers[header] = value
    return property(getter, setter, doc=('Retrieve    and    set    the    %s    property    in    the    WSGI    environ,    as    a    %s    object' % (header, cls.__name__)))

What's a good function header?

=====
Here's a good function header?
assistant
#Here's a good function header.

def _req_fancy_property(cls, header, even_if_nonexistent=False):