'Implement the ``&`` operator.
When used with SQL expressions, results in an
AND operation, equivalent to
:func:`~.expression.and_`, that is::
a & b
is equivalent to::
from sqlalchemy import and_
and_(a, b)
Care should be taken when using ``&`` regarding
operator precedence; the ``&`` operator has the highest precedence.
The operands should be enclosed in parenthesis if they contain
further sub expressions::
(a == 2) & (b == 4)'

def __and__(self, other):

    return self.operate(and_, other)
