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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 merge_map(a, b):
 """Recursively merge elements of argument b into argument a. Primarly used for merging two dictionaries together, where dict b takes precedence over dict a. If 2 lists are provided, they are concatenated. """

    if isinstance(a, list) and isinstance(b, list):
        return a + b

    if not isinstance(a, dict) or not isinstance(b, dict):
        return b

    for key in b:
        a[key] = merge_map(a[key], b[key]) if key in a else b[key]
    return a