>>> fetch_package_version('sentry')

def fetch_package_version(dist_name):
    """
    >>> fetch_package_version('sentry')
    """
    try:
        # Importing pkg_resources can be slow, so only import it
        # if we need it.
        import pkg_resources
    except ImportError:
        # pkg_resource is not available on Google App Engine
        raise NotImplementedError('pkg_resources is not available '
                                  'on this Python install')
    dist = pkg_resources.get_distribution(dist_name)
    return dist.version