The available columns for any given table are fetched from a system table called "sys_tablecolumns". A specific table name is provided in the WHERE criteria to restrict the table from which the column information is fetched:

import cdata.sapbusinesswarehouse as mod
conn = mod.connect("User=myuseraccount;Password=mypassword;URL=http://localhost:8000/sap/bw/xml/soap/xmla;")
cur = conn.cursor()
cmd = "SELECT * FROM sys_tablecolumns WHERE TableName = '[2CREPM_DEPSOV3].[2CREPM_DEPSOV3/2CREPM_DEPSOQV3].Customer'"
cur.execute(cmd)
rs = cur.fetchall()
for row in rs:
	print(row)