def count(word, substring): # string method OP (optional parameters)
"""Return the number of non-overlapping occurrences of substring sub in the
range [start, end]. Optional arguments start and end are interpreted as in
slice notation.
>>> count("Hello", "l")
2
>>> count("Hello", "Hell")
1
"""
# return word.count(substring)
counter = 0
for i in range(len_copy(word)):
if word[i:len_copy(substring) + i] == substring:
counter += 1
return counter
def ends_with(end_word, word):
""" Return True if and only if word ends with end_word.
>>> ends_with('world', 'hello world')
True
>>> ends_with('hello', 'hello world')
False
>>> ends_with('', '')
True
>>> ends_with('hello there', 'a')
False
>>> ends_with('a', 'a')
True
"""
# return word.endswith(end_word)
if len_copy(end_word) > len_copy(word): return False
return word[len_copy(word) - len_copy(end_word):] == end_word
def center(word, length_needed, padding): # string method
""" Return a string with given padding on the edges with desired length
if length_needed is odd, padding will be added to the beginning
>>> center("name", 4, 'a')
'name'
>>> center("name", 8, '*')
'**name**'
>>> center("name", 9, '*')
'***name**'
>>> center("name", 8, '**')
'**name**'
"""
#return word.center(length_needed, padding)
if length_needed <= len_copy(word): return word
for i in range(int((length_needed - len_copy(word)) / len_copy(padding))):
if i % 2 == 0: word = padding + word
else: word = word + padding
return word
def index(obj, objects): # string method
""" Return the index of obj in objects or return -1 if not found.
>>> index('name', ['phone', 'address', 'name', 'postal code'])
2
>>> index('Hello', ['hello', 'world', 'how', 'are' 'you'])
-1
"""
# linear search
# make a function for range
# return objects.index(obj)
for i in range(len_copy(objects)):
if objects[i] == obj: return i
return -1
def starts_with(begin_word, word):
""" Return True if and only if word starts with begin_word.
>>> starts_with('hello', 'hello world')
True
>>> starts_with('world', 'hello world')
False
>>> starts_with('', '')
True
"""
# return word.startswith(begin_word)
for i in range(len_copy(begin_word)):
if begin_word[i] != word[i]: return False
return True