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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 consolidate_dependencies(needs_ipython, child_program, requirement_files, manual_dependencies):
 """Parse files, get deps and merge them. Deps read later overwrite those read earlier."""

    # We get the logger here because it's not defined at module level
    logger = logging.getLogger('fades')

    if needs_ipython:
        logger.debug("Adding ipython dependency because --ipython was detected")
        ipython_dep = parsing.parse_manual(['ipython'])
    else:
        ipython_dep = {}

    if child_program:
        srcfile_deps = parsing.parse_srcfile(child_program)
        logger.debug("Dependencies from source file: %s", srcfile_deps)
        docstring_deps = parsing.parse_docstring(child_program)
        logger.debug("Dependencies from docstrings: %s", docstring_deps)
    else:
        srcfile_deps = {}
        docstring_deps = {}

    all_dependencies = [ipython_dep, srcfile_deps, docstring_deps]

    if requirement_files is not None:
        for rf_path in requirement_files:
            rf_deps = parsing.parse_reqfile(rf_path)
            logger.debug('Dependencies from requirements file %r: %s', rf_path, rf_deps)
            all_dependencies.append(rf_deps)

    manual_deps = parsing.parse_manual(manual_dependencies)
    logger.debug("Dependencies from parameters: %s", manual_deps)
    all_dependencies.append(manual_deps)

    # Merge dependencies
    indicated_deps = {}
    for dep in all_dependencies:
        for repo, info in dep.items():
            indicated_deps.setdefault(repo, set()).update(info)

    return indicated_deps