def _get_auth_header(self, oauth_params, realm=None):
"""Constructs and returns an authentication header."""
auth_header = 'OAuth realm="{realm}"'.format(realm=realm or "")
params = ""
for k, v in oauth_params.items():
params += ',{key}="{value}"'.format(key=k, value=quote(str(v)))
auth_header += params
return auth_header
def _escape(self, s):
'''
Escapes a string, ensuring it is encoded as a UTF-8 octet.
:param s: A string to be encoded.
:type s: str
'''
return quote(self._ensure_unicode(s), safe='~').encode('utf-8')
