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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(self, value, redis):
        '''
        Validates data obtained from a request and returns it in the apropiate
        format
        '''
        # cleanup
        if type(value) == str:
            value = value.strip()

        value = self.value_or_default(value)

        # validation
        self.validate_required(value)

        if self.regex and not re.match(self.regex, value, flags=re.ASCII):
            raise InvalidFieldError(self.name)

        if self.forbidden and value in self.forbidden:
            raise ReservedFieldError(self.name)

        if self.allowed and value not in self.allowed:
            raise InvalidFieldError(self.name)

        if self.index:
            key = self.key()

            old = debyte_string(redis.hget(key, value))
            old_value = getattr(self.obj, self.name)

            if old is not None and old != self.obj.id:
                raise NotUniqueFieldError(self.name)
            elif old_value != value:
                self.obj._old[self.name] = old_value

        return value