'Returns `True` if this unit is equivalent to ``other``.
Parameters
other : unit object or string or tuple
The unit to convert to. If a tuple of units is specified, this
method returns true if the unit matches any of those in the tuple.
equivalencies : list of equivalence pairs, optional
A list of equivalence pairs to try if the units are not
directly convertible.  See :ref:`unit_equivalencies`.
This list is in addition to the built-in equivalencies between the
function unit and the physical one, as well as possible global
defaults set by, e.g., `~astropy.units.set_enabled_equivalencies`.
Use `None` to turn off any global equivalencies.
Returns
bool'

def is_equivalent(self, other, equivalencies=[]):

    if isinstance(other, tuple):
        return any((self.is_equivalent(u, equivalencies=equivalencies) for u in other))
    other_physical_unit = getattr(other, u'physical_unit', (dimensionless_unscaled if self.function_unit.is_equivalent(other) else other))
    return self.physical_unit.is_equivalent(other_physical_unit, equivalencies)
