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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _validate_isvalid_quantity(self, isvalid_quantity, field, value):
 """Checks for valid given value and appropriate units. Args: isvalid_quantity (`bool`):
 flag from schema indicating quantity to be checked. field (`str`):
 property associated with quantity in question. value (`list`):
 list whose first element is a string representing a value with units The rule's arguments are validated against this schema: {'isvalid_quantity': {'type': 'bool'}, 'field': {'type': 'str'}, 'value': {'type': 'list'}} """

        quantity = Q_(value[0])
        low_lim = 0.0 * units(property_units[field])

        try:
            if quantity <= low_lim:
                self._error(
                    field, 'value must be greater than 0.0 {}'.format(property_units[field]),
                )
        except pint.DimensionalityError:
            self._error(field, 'incompatible units; should be consistent '
                        'with ' + property_units[field]
                        )