import StringIO,gzip
content = 'Life is short.I use python'
zbuf = StringIO.StringIO()
zfile = gzip.GzipFile(mode='wb', compresslevel=9, fileobj=zbuf)
zfile.write(content)
zfile.close()

f = gzip.open('file.gz', 'wb')
f.write(content)
f.close()

import gzip
with open("/path/to/file", 'rb') as plain_file:
  with gzip.open("/path/to/file.gz", 'wb') as zip_file:
    zip_file.writelines(plain_file)

from subprocess import check_call
check_call('gzip /path/to/file',shell=True)