For animation layer "AnimLayer1" you may get the attributes using maya.cmds:
import maya.cmds as cmds
print(cmds.animLayer("AnimLayer1", query=True, attribute=True))
[u'some_namespace:some_object.visibility', u'some_namespace:some_object.translateX', u'some_namespace:some_object.translateY', u'some_namespace:some_object.translateZ', u'some_namespace:some_object.rotateX', u'some_namespace:some_object.rotateY', u'some_namespace:some_object.rotateZ', u'some_namespace:some_object.scaleX', u'some_namespace:some_object.scaleY', u'some_namespace:some_object.scaleZ']
or with PyMel:
import pymel.core as pm
print(pm.animLayer("AnimLayer1", query=True, attribute=True))
[Attribute(u'some_namespace:some_object.visibility'), Attribute(u'some_namespace:some_object.translateX'), Attribute(u'some_namespace:some_object.translateY'), Attribute(u'some_namespace:some_object.translateZ'), Attribute(u'some_namespace:some_object.rotateX'), Attribute(u'some_namespace:some_object.rotateY'), Attribute(u'some_namespace:some_object.rotateZ'), Attribute(u'some_namespace:some_object.scaleX'), Attribute(u'some_namespace:some_object.scaleY'), Attribute(u'some_namespace:some_object.scaleZ')]