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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 clean_password(self, password, user=None):
 """ Validates a password. You can hook into this if you want to restric the allowed password choices. """

        min_length = app_settings.PASSWORD_MIN_LENGTH
        if min_length and len(password) < min_length:
            raise forms.ValidationError(_("Password must be a minimum of {0} "
                                          "characters.").format(min_length))
        validate_password(password, user)
        return password