def __setitem__(self, key, value):
        """
        Emplace file in cache.

        Arguments:
            key: Key.
            value (str): Path of file to insert in cache.

        Raises:
            ValueError: If no "value" does nto exist.
        """
        if not fs.exists(value):
            raise ValueError(value)

        path = self.keypath(key)
        fs.mkdir(self.path)
        fs.mv(value, path)
def __setitem__ ( self , key , value ) : if not fs . exists ( value ) : raise ValueError ( value ) path = self . keypath ( key ) fs . mkdir ( self . path ) fs . mv ( value , path )
Emplace file in cache.

        Arguments:
            key: Key.
            value (str): Path of file to insert in cache.

        Raises:
            ValueError: If no "value" does nto exist.