def sanitizer(unit):
    """
    Sanitizes a unit string. That is, it is de-blanked, and mu and µ symbols
    are changed to u for micro.

    :param unit: The unit that needs to be sanitized.

    :returns: the sanitized unit.
    :rtype: str
    """
    # micro = "\u03bc"
    micro = "µ"
    # mugr = "\u00b5"
    mugr = "μ"
    return unit.replace(" ", "").replace("mu", "u").\
        replace(micro, "u").replace(mugr, "u")