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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 ldd_deps(filename, ret=None):
    '''
    Recurse through a set of dependencies reported by ``ldd``, to find
    associated dependencies.

    Please note that this does not necessarily resolve all (non-package)
    dependencies for a file; but it does help.

    CLI Example:

        salt myminion genesis.ldd_deps bash
        salt myminion genesis.ldd_deps /bin/bash
    '''
    if not os.path.exists(filename):
        filename = salt.utils.path.which(filename)

    if ret is None:
        ret = []

    out = __salt__['cmd.run'](('ldd', filename), python_shell=False)
    for line in out.splitlines():
        if not line.strip():
            continue
        dep_path = ''
        if '=>' in line:
            comps = line.split(' => ')
            dep_comps = comps[1].strip().split()
            if os.path.exists(dep_comps[0]):
                dep_path = dep_comps[0]
        else:
            dep_comps = line.strip().split()
            if os.path.exists(dep_comps[0]):
                dep_path = dep_comps[0]

        if dep_path:
            if dep_path not in ret:
                ret.append(dep_path)
                new_deps = ldd_deps(dep_path, ret)
                for dep in new_deps:
                    if dep not in ret:
                        ret.append(dep)

    return ret