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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 find_copy_constructor(type_):
 """ Returns reference to copy constructor. Args: type_ (declarations.class_t):
 the class to be searched. Returns: declarations.constructor_t: the copy constructor """

    copy_ = type_.constructors(
        lambda x: is_copy_constructor(x),
        recursive=False,
        allow_empty=True)
    if copy_:
        return copy_[0]

    return None