Problem with c3d import

Dear Experts !

I am using:
-Blender version 2.79
-import_c3d : “author”: “Daniel Monteiro Basso [email protected]”, “version”: (2015, 5, 5, 1), “blender”: (2, 74, 1)

I would like to write a Python script which goes apply data from file c3d to an armature into bvh.
I believe the subject is familiar but my problem is : the data of the file c3d is not imported.

I am trying import Motion Capture files of extension .c3d to Blender via Python command : bpy.ops.import_anim.c3d(filepath=myfilepath).

Via a linux terminal, for every keyframe, the positions of bones of the skeleton_import_c3d are (0, 0, 0) and the animation_data is none.

Can you explain me how to get the animation_data from my file skeleton.c3d please ??

I specify one thing, my file skeleton.c3d that i use, works.
When i import manually to Blender like “File-> Import -> Graphics Labs Motion Capture (.c3d)-> myfile.c3d” , it works ! I have my skeleton_imported with positions, animation, keyframes, actions with values as Blender GUI shows them.

Here my script:

import bpy

bpy.ops.import_anim.c3d(filepath=myfilepath)

skeleton_c3d_import = bpy.context.scene.objects.active

for obj in bpy.context.scene.objects:
print("obj: ",obj)

for bone in skeleton_c3d_import.pose.bones:
print(bpy.context.scene.objects.active, bone.name, bone.location)

print("skeleton_c3d_import.animation_data: ",skeleton_c3d_import.animation_data)

And the results are:

<bpy_struct, Object(“skeleton.c3d”)> 00 <Vector (0.0000, 0.0000, 0.0000)>
<bpy_struct, Object(“skeleton.c3d”)> 01 <Vector (0.0000, 0.0000, 0.0000)>
<bpy_struct, Object(“skeleton.c3d”)> 02 <Vector (0.0000, 0.0000, 0.0000)>
<bpy_struct, Object(“skeleton.c3d”)> 03 <Vector (0.0000, 0.0000, 0.0000)>

skeleton_c3d_import.animation_data: None

???