Impacted versions:10

Steps to reproduce:
Following the code in https://www.odoo.com/documentation/10.0/api_integration.html both in a fresh install and against 'https://demo.odoo.com/start' trows a type error

Current behavior:
Now I get an error when executing:

```
ids = models.execute_kw(db, uid, password,  'res.partner', 'search',
    [[['is_company', '=', True], ['customer', '=', True]]],
    {'limit': 1})
[record] = models.execute_kw(db, uid, password,
    'res.partner', 'read', [ids])
# count the number of fields fetched by default
len(record)
```

In particular it seems to be a type error (cannot marshal class odoo.tools.float_utils.float_precision)

Expected behavior:
I would expect it to behave as in the documentation

return record.env[self.comodel_name]._browse(value, record.env, record._prefetch)
    def convert_to_read(self, value, record, use_name_get=True):
        if use_name_get and value:
            
            
            
            try:
                
                return value.sudo().name_get()[0]
            except MissingError:
                
                return False
        else:
            return value.id
    def convert_to_write(self, value, record):
        return value.id
    def convert_to_export(self, value, record):
        return value.name_get()[0][1] if value else ''
    def convert_to_display_name(self, value, record):
        return ustr(value.display_name)
    def convert_to_onchange(self, value, record, fnames=()):
        if not value.id:
            return False
        return super(Many2one, self).convert_to_onchange(value, record, fnames)
class UnionUpdate(SpecialValue):