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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _update_bcbiovm():
 """Update or install a local bcbiovm install with tools and dependencies. """

    print("## CWL support with bcbio-vm")
    python_env = "python=3"
    conda_bin, env_name = _add_environment("bcbiovm", python_env)
    channels = _get_conda_channels(conda_bin)
    base_cmd = [conda_bin, "install", "--yes", "--name", env_name] + channels
    subprocess.check_call(base_cmd + [python_env, "nomkl", "bcbio-nextgen"])
    extra_uptodate = ["cromwell"]
    subprocess.check_call(base_cmd + [python_env, "bcbio-nextgen-vm"] + extra_uptodate)