import svn.core    
import svn.client    

svn.core.apr_initialize()

pool = svn.core.svn_pool_create(None)
ctx = svn.client.svn_client_create_context(pool)
#ctx.auth_baton = svn_auth_open()
ctx.config = svn.core.svn_config_get_config("ughdir", pool)

revision = svn.core.svn_opt_revision_t()
revision.kind = svn.core.svn_opt_revision_head
svn.client.svn_client_checkout("https://a", ".", revision, True, ctx, pool)