def make_file_url(self, share_name, directory_name, file_name,<EOL>protocol=None, sas_token=None):
if directory_name is None:<EOL><INDENT>url = '<STR_LIT>'.format(<EOL>protocol or self.protocol,<EOL>self.primary_endpoint,<EOL>share_name,<EOL>file_name,<EOL>)<EOL><DEDENT>else:<EOL><INDENT>url = '<STR_LIT>'.format(<EOL>protocol or self.protocol,<EOL>self.primary_endpoint,<EOL>share_name,<EOL>directory_name,<EOL>file_name,<EOL>)<EOL><DEDENT>if sas_token:<EOL><INDENT>url += '<STR_LIT:?>' + sas_token<EOL><DEDENT>return url<EOL>
Creates the url to access a file.

:param str share_name:
    Name of share.
:param str directory_name:
    The path to the directory.
:param str file_name:
    Name of file.
:param str protocol:
    Protocol to use: 'http' or 'https'. If not specified, uses the
    protocol specified when FileService was initialized.
:param str sas_token:
    Shared access signature token created with
    generate_shared_access_signature.
:return: file access URL.
:rtype: str