def _combine(self, old_self, other, blend=True):
if blend:<EOL><INDENT>self.components = old_self.components.copy()<EOL>for c in other.components:<EOL><INDENT>if c not in self.components:<EOL><INDENT>self.components.append(c)<EOL><DEDENT><DEDENT>self.description = old_self._blend_descriptions(other)<EOL>self.data = old_self._combine_data(other)<EOL><DEDENT>else:<EOL><INDENT>self.components = other.components<EOL>self.description = other.description<EOL>self.data = other.data<EOL><DEDENT>return self<EOL>
Private method. Combines data, components, and descriptions but
nothing else.

Args:
    old_self (Interval): You have to pass the instance explicitly.
    other (Interval): The other Interval.
    blend (bool): Whether to blend or not.

Returns:
    Interval. The combined description.