def _is_iterable(val):
    """
    Checks if the input if an iterable. This function will return False if a
    string is passed due to its use in pmutt.

    Parameters
    ----------
        val : iterable or non-iterable
            Value to check if iterable
    Returns
    -------
        is_iterable : bool
            True if iterable. False if not iterable or string.
    """
    if isinstance(val, str):
        return False
    else:
        # If it's not a string, check if it's iterable
        try:
            iter(val)
        except TypeError:
            return False
        else:
            return True