'Convert ``elem`` into the internal representation.
This method is called implicitly whenever computations involve elements
not in the internal representation.
>>> from sympy.abc import x
>>> from sympy import QQ
>>> F = QQ.old_poly_ring(x).free_module(2) / [(1, 2), (1, x)]
>>> F.convert([1, 0])
[1, 0] + <[1, 2], [1, x]>'

def convert(self, elem, M=None):

    if isinstance(elem, QuotientModuleElement):
        if (elem.module is self):
            return elem
        if self.killed_module.is_submodule(elem.module.killed_module):
            return QuotientModuleElement(self, self.base.convert(elem.data))
        raise CoercionFailed
    return QuotientModuleElement(self, self.base.convert(elem))
