<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def render_constants():
 """render generated constant files from templates"""

    generate_file("constant_enums.pxi", cython_enums, pjoin(root, 'zmq', 'backend', 'cython'))
    generate_file("constants.pxi", constants_pyx, pjoin(root, 'zmq', 'backend', 'cython'))
    generate_file("zmq_constants.h", ifndefs, pjoin(root, 'zmq', 'utils'))