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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 _check_conditional_statement(statement, num_collections):
 """Method to check conditional statements to be sure that they are valid. Args: statement: A conditional statement as a string (e.g. a>25 and a%5==0). The variable should always be named as 'a' (without quotations). num_collections: An integer representing the number of data collections that the statement will be evaluating. Return: correct_var: A list of the correct variable names that should be used within the statement (eg. ['a', 'b', 'c']) """

        # Determine what the list of variables should be based on the num_collections
        correct_var = list(ascii_lowercase)[:num_collections]

        # Clean out the operators of the statement
        st_statement = BaseCollection._remove_operators(statement)
        parsed_st = [s for s in st_statement if s.isalpha()]

        # Perform the check
        for var in parsed_st:
            if var not in correct_var:
                raise ValueError(
                    'Invalid conditional statement: {}\n '
                    'Statement should be a valid Python statement'
                    ' and the variables should be named as follows: {}'.format(
                        statement, ', '.join(correct_var))
                    )
        return correct_var