def get_version(version=None):
	"Returns a PEP 440-compliant version number from VERSION."
	version = get_complete_version(version)
	main = get_main_version(version)
	sub = ""
	if version[3] == "alpha" and version[4] == 0:
		git_changeset = get_git_changeset()
		if git_changeset:
			sub = ".dev%s" % git_changeset
		else:
			sub = ".dev"
	elif version[3] != "final":
		mapping = {"alpha": "a", "beta": "b", "rc": "rc"}
		sub = mapping[version[3]] + str(version[4])
	return str(main + sub)
def get_main_version(version=None):
	"Returns main version (X.Y[.Z]) from VERSION."
	version = get_complete_version(version)
	parts = 2 if version[2] == 0 else 3
	return ".".join(str(x) for x in version[:parts])
def get_complete_version(version=None):
	"""Returns a tuple of the graphql version. If version argument is non-empty,
    then checks for correctness of the tuple provided.
    """
	if version is None:
		pass
	else:
		assert len(version) == 5
		assert version[3] in ("alpha", "beta", "rc", "final")
	return version
def get_docs_version(version=None):
	version = get_complete_version(version)
	if version[3] != "final":
		return "dev"
	else:
		return "%d.%d" % version[:2]
def get_git_changeset():
	"""Returns a numeric identifier of the latest git changeset.
    The result is the UTC timestamp of the changeset in YYYYMMDDHHMMSS format.
    This value isn't guaranteed to be unique, but collisions are very unlikely,
    so it's sufficient for generating the development version numbers.
    """
	repo_dir = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
	try:
		git_log = subprocess.Popen("git log --pretty=format:%ct --quiet -1 HEAD", stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True, cwd=repo_dir, universal_newlines=True)
		timestamp = git_log.communicate()[0]
		timestamp = datetime.datetime.utcfromtimestamp(int(timestamp))
	except Exception:
		return None
	return timestamp.strftime("%Y%m%d%H%M%S")