Mirrors a file to a different location. Each time the file changes
           while the process is running it will be copied to 'path_to',
           overwriting the destination.

        Parameters
        ----------
        path_to : string
            The mirror destination.

        path_from : string
            The mirror origin.

        from_quick_server : bool
            If set the origin path is relative to *this* script otherwise it is
            relative to the process.

def mirror_file(self, path_to, path_from, from_quick_server=True):
        """Mirrors a file to a different location. Each time the file changes
           while the process is running it will be copied to 'path_to',
           overwriting the destination.

        Parameters
        ----------
        path_to : string
            The mirror destination.

        path_from : string
            The mirror origin.

        from_quick_server : bool
            If set the origin path is relative to *this* script otherwise it is
            relative to the process.
        """
        full_path = path_from if not from_quick_server else os.path.join(
            os.path.dirname(__file__), path_from)
        if self._mirror is None:
            if not self._symlink_mirror(path_to, full_path, init=True):
                self._poll_mirror(path_to, full_path, init=True)
            return
        impl = self._mirror["impl"]
        if impl == "symlink":
            self._symlink_mirror(path_to, full_path, init=False)
        elif impl == "poll":
            self._poll_mirror(path_to, full_path, init=False)
        else:
            raise ValueError("unknown mirror implementation: {0}".format(impl))