'Initializes on a source and target SpatialReference objects.'

def __init__(self, source, target):

    if ((not isinstance(source, SpatialReference)) or (not isinstance(target, SpatialReference))):
        raise TypeError('source    and    target    must    be    of    type    SpatialReference')
    self.ptr = capi.new_ct(source._ptr, target._ptr)
    self._srs1_name = source.name
    self._srs2_name = target.name
