def floatformatter(*args, sig: int=6, **kwargs) -> str:
    """
    Returns a formatter, which essantially a string temapate
    ready to be formatted.
    
    Parameters
    ----------
    sig : int, Optional
        Number of significant digits. Default is 6.
        
    Returns
    -------
    string
        The string to be formatted.
    
    Examples
    --------    
    >>> from dewloosh.core import Library
    >>> data = Library()
    >>> data['a']['b']['c']['e'] = 1
    >>> data['a']['b']['d'] = 2
    >>> data.containers()
            
    """
    return "{" + "0:.{}g".format(sig) + "}"