def install_pip(self, package, save=True, save_dev=False):
        """Installs a pip package.

        :param save: if `True`, pins the package to the Hydrogen requirements
            YAML file.
        :param save_dev: if `True`, pins the package as a development
            dependency to the Hydrogen requirements YAML file.
        :param return: a **single** :class:`Requirement` object, representing
            the installed version of the given package.
        """
        requirement = Requirement.coerce(package)
        click.echo("pip install " + requirement.package)
        cmd = envoy.run("pip install {}".format(str(requirement)))
        if cmd.status_code == 0:
            installed_packages = get_installed_pypackages()
            package = installed_packages[requirement.package]
            requirement.version = "=={}".format(package.version)
            if save:
                self.requirements["all"].add(requirement)
            if save_dev:
                self.requirements["dev"].add(requirement)
            if save or save_dev:
                self.requirements.save()
            return requirement
        else:
            fatal(cmd.std_err)
def _match_notequal_to(search_base, attribute, value, candidates):
        matches = list()
        match_using_regex = False

        if "*" in value:
            match_using_regex = True
            #regex = check_escape(value)
            regex = value.replace('*', '.*')
            regex = "^{0}$".format(regex)

        for entry in candidates:
            found = False
            dn = entry.get("dn")

            if not dn.endswith(search_base):
                continue

            values_from_directory = entry.get("attributes").get(attribute)
            if isinstance(values_from_directory, list):
                for item in values_from_directory:
                    if attribute == "objectGUID":
                        item = _convert_objectGUID(item)

                    if match_using_regex:
                        m = re.match(regex, str(item), re.I)
                        if m:
                            found = True
                    else:
                        if item == value:
                            found = True
                if found is False:
                    entry["type"] = "searchResEntry"
                    matches.append(entry)
            else:
                if attribute == "objectGUID":
                    values_from_directory = _convert_objectGUID(values_from_directory)

                if match_using_regex:
                    m = re.match(regex, str(values_from_directory), re.I)
                    if not m:
                        entry["type"] = "searchResEntry"
                        matches.append(entry)
                else:
                    if str(value) != str(values_from_directory):
                        entry["type"] = "searchResEntry"
                        matches.append(entry)

        return matches