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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 retrieve_import_alias_mapping(names_list):
 """Creates a dictionary mapping aliases to their respective name. import_alias_names is used in module_definitions.py and visit_Call"""

    import_alias_names = dict()

    for alias in names_list:
        if alias.asname:
            import_alias_names[alias.asname] = alias.name
    return import_alias_names