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Python code to replace characters in between % %.
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Here is a Python code to replace characters in between % %%

import string

def replace_in_between(text, start, end, replacement):
    """Replace characters in between % %.

    :param str text:
    :param int start:
    :param int end:
    :param str replacement:
    :rtype: str
    :return:
    """
    return text[:start] + replacement + text[end:]

# Enter the text
text = "This is a test"

# Enter the start and end
start = 1
end = 5

# Enter the replacement
replacement = "This is a test"

# Calling the function
print((replace_in_between(text, start, end, replacement)))

#Example Output
# TThis is a testis a test

#Remember to inspect code for bugs.